Sinn Féin leader Gerry Adams has called for a referendum on Irish unity in the next five years.

Mr Adams has also said he will seek re-election as the party president in November and then outline his own future intentions.

He told a meeting of his party's elected representatives that he will set out the "planned process of generational change" at the party's Ard Fheis.

Mr Adams said too that the party wants to be in government.

"We have no ambition to be part of the system. Our ambition is to change it. That means we must be in government - North and South," he said.

However, the Sinn Féin leader insisted there will be no return to the Assembly or Executive at Stormont without a stand-alone Irish Language Act.

Mr Adams was speaking at the start of the Sinn Féin think-in ahead of the Dáil resuming later this month.

The two-day meeting in Co Meath is likely to focus on the current talks aimed at restoring power-sharing in Northern Ireland.

It is just over a fortnight until the Dáil meets for the first time since the summer break, but the political parties will this week begin planning for the new term.

It is expected there will also be a focus on the next general election, with the party honing policies on health and housing, two of the issues expected to dominate debate in Leinster House this autumn.

Budget Day will come just three weeks after the Dáil term begins and Sinn Féin is adamant that any extra money available on 10 October should not be used for tax cuts.

There will also be a spotlight today on the party's view about possibly entering coalition after the next election.

This evening, Mr Adams said that filling the jails again for the thousands of offences carried out during the Troubles would not be helpful to the political process in Northern Ireland.

He was responding to questions about a garda review of the murder of Louth farmer Tom Oliver by the IRA in 1991.

He said there were two imperatives, one was to support the Oliver family and the other was to support the Good Friday Agreement.

He said that under that agreement political prisoners were released after two years.

DUP and Alliance reject Irish unity poll proposal

Two of Northern Ireland's parties have rejected the proposal by Mr Adams that a poll on Irish unity should be held within five years.

The DUP and the Alliance Party outlined their views after they held talks with Minister for Foreign Affairs and Trade Simon Coveney at Stormont this afternoon.

Simon Hamilton of the DUP said: "We are supremely optimistic that a border poll would not succeed and that the people of Northern Ireland would vote to remain part of the United Kingdom but the experience of Scotland is that such a referendum could be destabilising to the body politic, to the economy and wider society and we don't believe it is wise at this time."

Stephen Farry of the Alliance Party said he does not see any evidence in Northern Ireland that there would be any likelihood of change on the constitutional question so there is no basis for the Secretary of State to call a border poll either this year or in five years' time.

He said he sees this as being a major distraction from the work in hand of building a united, coherent Northern Ireland.

He said they have to bring people together and that means that while they have to respect people's different constitutional aspirations, the priority has to be the reconciliation process and building a shared future and putting back self-government that is sustainable.

But the Alliance Party did confirm it supports the Sinn Féin position that a stand-alone Irish language act should be part of an agreement to restore power-sharing.

This means that with the support of the SDLP and the Alliance Party, Sinn Féin has a majority of the Assembly's 90 members favouring the stand alone act approach.

The party's Mr Farry told journalists this afternoon: "We do support a stand-alone Irish Language Act. That is probably the only way we are going to get an agreement about the restoration of power-sharing.

"As for the content, we are looking for something that is proportionate and realistic and that would not be what has been suggested by Sinn Féin."