The Taoiseach has said that he expects "many twists and turns" in relation to Brexit between now and 31 October.
Leo Varadkar was speaking in Drogheda where he was attending the annual Fleadh Cheoil na hÉireann.
Mr Varadkar said he will ask the British Prime Minister how the UK will honour the commitments it made to Ireland in December 2017 about avoiding a hard border on the island of Ireland if the Withdrawal Agreement is not something he can accept when the pair speak early next week.
The Taoiseach confirmed he is due to speak by phone to Boris Johnson before Mr Johnson meets the French and German leaders in the run up to the G7 meeting next week.
And he said he expects to meet the British Prime Minister in person in early September.
The meeting will be their first face-to-face encounter since Mr Johnson became prime minister.
Meanwhile, Jeremy Corbyn's proposal to be installed as caretaker prime minister to prevent a no-deal Brexit has received a further blow after another senior Tory ruled out backing the plan.
Oliver Letwin said he would not be able to support a bid to put the Labour leader in Number 10, saying he did not think it was likely that a majority could be formed for the idea.
The Conservative former minister, who was among recipients of a letter from Mr Corbyn outlining his plan, said it was "well worth" having discussions across the Commons to prevent the UK crashing out of the EU without a deal.
But, when asked if he would make the Leader of the Opposition prime minister, he told BBC Radio 4's Today programme: "That appears to be his agenda, I have to say it is not one I personally share.
"I don't think it's at all likely that a majority would be formed for that and I personally wouldn't want to vote for it. I wouldn't be able to support that, no."
However, Mr Letwin did not rule out supporting a no confidence motion to bring down the Tory government to prevent a no-deal, but said he would not back it if it led to Mr Corbyn becoming prime minister.
He said: "I'm not very inclined to do that if it could possibly be avoided - it's not something I would do under any circumstances in normal life and I'd much prefer to find some other means of getting to a substantive result."
It comes after Conservative grandee Ken Clarke said he would be willing to lead a government of national unity to avoid a no-deal Brexit - after Liberal Democrat leader Jo Swinson suggested an emergency government be led by him or Labour's Harriet Harman.
Mr Clarke said it was "not inconceivable" that a government of national unity may be needed to resolve the impasse, suggesting politics was in a similar situation to 1931 and the two world wars.
He told BBC Radio 4's PM programme: "If it was the only way in which the plain majority in the House of Commons that is opposed to a no-deal exit could find a way forward... I wouldn't object to it, if that was the judgment of people, the only way forward."
Ms Swinson's proposal came after she rejected Mr Corbyn's suggestion that he could lead an emergency government to thwart a no-deal Brexit, despite agreeing to meet with him to discuss a no-deal prevention plan.
Anna Soubry, leader of the Independent Group, confirmed that she would also "not support nor facilitate any government led by Jeremy Corbyn".
But Mr Corbyn's plan has won the potential backing of the SNP, Plaid Cymru and Tory MP Guto Bebb.
SNP leader Nicola Sturgeon was among those applying pressure to Ms Swinson to re-think her position.
Mr Letwin and fellow senior Remain-supporting Tory Dominic Grieve, as well as independent MP Nick Boles, have agreed to meet Mr Corbyn.