The long drawn out battle to determine who becomes the next President of the European Commission has suffered another setback, with the Dutch Prime Minister Mark Rutte describing the process as "unbelievably complicated."

So what happens now and why is Europe so divided on the issue?

Today the Dutch Socialist Frans Timmermans emerged as a possible compromise candidate to become the next President of the European Commission. But it wasn't long before his detractors, many of whom are from the the so-called "Visegrad Four" countries of Hungary, Poland, Slovakia and the Czech Republic made it clear they could not support him. 

The summit which lasted all night, is the third attempt to fill three of the top posts in the world's biggest free-trading area, home to over 500 million people.

A spokesperson for European Council President Donald Tusk confirmed this morning that talks had been suspended, with negotiations set to reconvene tomorrow morning at 11am.

Record talks

The talks have already broken records as the longest ever set of talks at an EU summit.

Giving his reaction to the deadlock, Spain's Prime Minister Pedro Sanchez said that none of the three lead candidates for the top jobs in the EU had enough support. "We need to start again," he told reporters.

The Netherlands Prime Minister Mark Rutte described the process as "unbelievably complicated" and said it was not certain as to whether a decision will be made by tomorrow.

He declined to comment on the strength of Mr Timmermans candidacy, saying "You have so many political factions". He added that some of the factions remain divided among themselves.

French President Emmanuel Macron, who left the venue shortly after the talks were called off, labelled them a "failure". However he struck a cautiously optimistic note, saying he is confident a deal can be reached by tomorrow. 

The failure to find consensus has reflected the fragmented state of the bloc's parliament which has also struggled to reach a common position on issues from migration to climate chance.

And as the long drawn out process continues, some diplomats have warned that any further delays could provide more ammunition for anti-establishment nationalists who have claimed the EU is out of touch.

Why the intense battle for the Commission?

A senior EU official has said the major sticking point in agreeing top European jobs is the position of President of the European Commission. The spokesman said that relations were polarised along party political lines "which had certainly complicated a compromise".

All of the four main political "families" in the European Parliament - the conservative European People's Party, the socialist S&D, the Liberals and the Greens have all been vying for their slice of the cake, with Jean-Claude Juncker's post as head of the executive Commission arguably the most powerful and sought after.

Whoever is appointed as the next Commission President will need the support of at least 72% of the 28 member states, who must represent at least 65% of the bloc's population.

The EPP rebellion

Mr Timmerman's apparent rise to the top of the pile comes at the expense of Manfred Weber, the man the European People's Party (EPP) had wanted to lead the Commission.

But Mr Weber faced stiff opposition from France and Spain. If Mr Timmermans is successful, it would be a major victory for Mr Macron, who had criticised Mr Weber's lack of executive experience.

Frans Timmermans

In a compromise deal, Mr Weber could now head the European Parliament, but perhaps for just half of the usual five-year term.

Over the weekend the leaders of France, Germany, Spain and the Netherlands met on the fringes of the G20 summit in Osaka in an effort to find a compromise.

The 'Osaka deal' would see the Parliament's largest political group, the centre-right EPP take the European Parliament role, along with a role heading up the EU's foreign policy.

However the EPP has refused to accept this compromise deal. It repeated that their "Spitzenkandidat" Manfred Weber had won the European Elections of 26 May.

The rebellion by the EPP has underlined the weakness of German Chancellor Angela Merkel amid suggestions that she does not have full control of her Christian Democrat party, which is part of the EPP group. 

Brigid Laffan, Director of the Global Governance Programme at the European University Institute in Florence says: "There continues to be a significant part of the EPP who oppose Timmermans or not so much oppose him as favour an EPP person. But I can't see the circumstances in which there will be agreement on Manfred Weber as Commission President."

She believes Mr Timmermans could yet maintain his position as the preferred option: "Firstly he was a Spitzenkandidat, so he stood for the socialists in the election, he engaged in the debates, he has a very strong track record as First Vice President of the Commission, he's extremely experienced and he did a lot to uphold the Rule of Law."

Opposition from eastern central Europe

Significantly, Mr Timmermans also faces opposition from eastern Europe. For the last five years, he has been the first Vice President of the European Commission with responsibility for the Rule of Law.

This brief has seen him clash with the governments of Hungary, Poland and Romania over their progress in this area. The Czech Prime Minister Andrej Babiš has also questioned Mr Timmerman's respect for central and eastern European countries.

The Croatian Prime Minister Andrej Plenković said yesterday "Everything is open", insisting that Mr Timmermans was not the only candidate being considered.

The Polish Prime Minister Mateusz Morawiecki indicated that Italy had joined in their opposition to Mr Timmermans and he said differences between the bloc's national leaders were still "very wide."

He warned that such a momentous decision should not be forced on reluctant countries as this could undermine the EU's future cohesion.

Professor Laffan adds: "I think that for the countries of east central Europe he's seen as problematic, but why should he be seen as problematic when he's upholding the EU treaties? But I do understand that's a source of opposition."

Why Ireland will be keeping a close watch on this race

The Fine Gael party is a member of the EPP and Taoiseach Leo Varadkar said last night that the majority of EPP leaders did not wish to give up the Commission Presidency without a fight.

He said: "I think its fair to say there's a lot of oppostion to the proposal that was made in Osaka from the EPP's point of view."

However Professor Laffan says she is surprised that Ireland had not shown more support for Mr Timmermans.

"That really does surprise me. It must be that the Taoiseach feels that an EPP candidate should get a better job in this package, but I think from an Irish point of view, he would make a good Commission President. He is credible and experienced and he would maintain the Spitzenkadidaten process."

Leo Varadkar arriving for the Brussels summit

She also believes that Mr Timmermans would be a good negotiator when it comes to Brexit.

"I think he would be pretty orthodox in terms of the position of the Commission and from our point of view, orthodox is good because effectively he would not be one to want to undermine the Backstop in any way. But I don't see any Commission president wanting to do that at this juncture."

She says his excellent command of the English language could also help in any future negotiations with Britain.

"He is an Anglophile, he speaks impeccable English. It's very difficult when listening to him to think that he is not in fact English so it could well be that in terms of discussion he might change the tone but not the substance."

Mr Timmermans has also said he would like to make fairer taxation one of his priorities. This includes a call during a Presidential debate in May for a minimum corporation tax rate of 18% across the EU, something that would have serious implications for Ireland where the current corporation tax rate is 12.5%.

What happens next?

Brigid Laffan says that what will happen next is not fully clear, but "a balance will have to be found by geography, by gender and by experience.

"The other person who I think might fulfil the criteria would be the Danish Commissioner Margrethe Vestager."

But she adds: "She of course has a certain notoriety in Ireland because she used Competition law against Apple."

She says she is reasonably certain that a compromise can be reached as a qualified majority rather than unanimity is needed for the European Council to agree on this issue. 

"So the question is will there be enough countries supporting a candidate for the Commission? If not, the European Parliament will have to elect its President this week and by electing its President without a Commission President nominee already, then the Council hands over the initiative to the Parliament and I'm not sure they'll want to do that."

Ms Laffan  says that by waiting until 11am tomorrow, European Council President Donald Tusk is giving countries time to reflect, but adds: "They have every incentive to agree by tomorrow."