Tánaiste Simon Coveney has said that a no-deal Brexit is now a real risk because the UK is looking for something different to what was committed in the Political Declaration.
Speaking on RTÉ's The Week in Politics, Mr Coveney said that there will be difficulties as long as the UK want to effectively deregulate their economy, while continuing to have access to the EU Single Market.
Tánaiste @simoncoveney says a no-deal Brexit is a risk now because the UK is looking for something very different to what was committed to in the Political Declaration #rtetwip pic.twitter.com/cxFc89YkTG— The Week in Politics (@rtetwip) May 17, 2020
"It’s a risk that’s for sure, this is the third round of negotiations completed in the week just passed, they didn’t go well, as the previous rounds didn’t either and its essentially as the two sides are looking for different things.
"The UK is essentially rewriting what was committed to previously in the Political Declaration that was signed off along with the Withdrawal Agreement," he said.
He said the UK had to move on the level playing field issue to break the deadlock.
"Until the UK changes its approach in the context of giving the EU assurance that they are not going to effectively deregulate their economy while expecting free access in the EU single market, I think we're going to continue to be in real difficulty in these talks," he added.
Meanwhile, UK cabinet minister Michael Gove has said there was a post-Brexit trade deal to be done with the EU, providing the bloc agreed to compromise.
The UK left the EU on 31 January but the main terms of its membership remain in place for a transition period until the end of this year to allow it time to negotiate a free trade agreement.
Both Britain's and the EU's chief negotiators on Friday gave downbeat assessments of the latest round of talks, saying the other side had to give ground if any progress was to be made.
The stalemate has raised the prospect that there will be no deal struck, a scenario that would damage global trade as the world copes with the economic fallout from the coronavirus pandemic.
The main sticking point in the talks has been so-called "level playing field" rules to ensure fair competition.
The EU says they are indispensable to ensure Britain does not undercut its standards, but Britain rejects them as binding it to European laws.
Mr Gove, the British Cabinet Office Minister, said this and issues such as future fishing rights remained sticking points.
"We're making it clear to the EU we can't do a deal on those terms," he told Sky News. "But I am confident that there is a deal to be done. It just requires a degree of flexibility on the EU side which I'm sure that they will appreciate they need to show."
Britain's Mail on Sunday newspaper reported that the government was preparing to walk away altogether if no progress was made at the next round of talks due to begin in 15 days time and if the EU did not shift.
"Breakdown is entirely possible," an unnamed senior government source told the paper.
The Sunday Times said a no-deal planning committee, chaired by Mr Gove, was now going to meet regularly and that officials who had been seconded to help fight the Covid-19 outbreak were being moved back to plan for this eventuality.
Elsewhere, the EU's chief Brexit negotiator, Michel Barnier, has been told there is "significant opposition" to the United Kingdom government's refusal to consider extending the timetable for talks.
Both the Scottish National Party's Westminster leader, Ian Blackford, and the interim Liberal Democrats leader, Ed Davey, have signed a letter to Mr Barnier supporting an extension to the transition period.
Such a move, they said, would allow talks to take place when "the efforts of national governments and the European Union will not be engaged solely with dealing with the dreadful Covid-19 epidemic".
The letter to Mr Barnier has also been signed by the leader of the SDLP, Colum Eastwood, and the Alliance Party MP, Stephen Farry, as well as the Plaid Cymru MP, Liz Saville Roberts, and the Green MP, Caroline Lucas.
They contacted Mr Barnier to highlight the "significant opposition to the UK Government's extreme position amongst the business community, the general public and elected representatives".
The opposition MPs noted the Scottish and Welsh governments both backed an extension of the transition period, along with "the majority of political parties in the Northern Ireland Executive".
The MPs said: "A consensus is taking shape and we hope the UK Government will soon recognise reality.
"It is now in all of our common interests to agree and secure an extension to the transition period. This will enable these detailed and defining negotiations to be conducted at a time when, we hope, the efforts of national governments and the European Union will not be engaged solely with dealing with the dreadful Covid-19 epidemic."
SNP Westminster leader Ian Blackford said they had written to Mr Barnier because "time is running out until we hit the hard Brexit deadline".
He insisted: "It is vital that the Tory government does the only responsible thing and accepts a two-year extension to the transition period."
Mr Blackford continued: "Crashing out with a bad deal or no deal in the middle of the coronavirus crisis, would deal a double hammer blow to the economy just when we will need all the help we can get to save jobs, businesses and living standards."
But he claimed: "It increasingly appears the Tory government is intent on taking Scotland and the UK down the path of a devastating no-deal. That would be beyond reckless.
"The coronavirus economic crash is the worst in living memory. People and businesses are already struggling to get by. The Tory government must put its responsibilities to the economy ahead of its Brexit obsession.
"Polls consistently show that the overwhelming majority of people in Scotland and across the UK want to see an extension to the Brexit transition period - and there is growing consensus across political parties.
"It's time for the UK Government to act," he said.