Boris Johnson: Dublin plays the waiting game over new PM
Politicians in Dublin are playing the waiting game - waiting for the real Boris Johnson to step forward before passing judgement on the new PM.
They have listened to his hardening Brexit stance and his pledge to leave the EU without a deal come 31 October if there is no agreement.
But they know he has a habit of breaking political promises.
They remember how the new PM lambasted the backstop and Theresa May's deal before voting for it four months later.
But now the chief Brexit cheerleader has become the chief Brexit strategist, the Irish government is choosing its words carefully.
In congratulating Boris Johnson, Taoiseach (Irish PM) Leo Varadkar said he was looking forward to "early engagement" on Brexit.
Speaking to RTÉ, the Irish national broadcaster, on Wednesday he said: "Confidence and enthusiasm are not a substitute for a European policy or a foreign policy, so we'll need to hear in detail what he has in mind."
He added that his impression was that Mr Johnston was "not just talking about deleting the backstop", but that he was proposing "a whole new deal, a better deal for Britain - that's not going to happen".
The taoiseach stressed that the European Council has no plans to meet before the scheduled date of 12 October, "so any suggestion that there could be a whole new deal negotiated in weeks or months is not in the real world".
Asked about the prospect of a no-deal Brexit, Mr Varadkar said: "One thing I am confident about... is that there are enough people in the British parliament who won't do that to their country and I still believe it's very unlikely."
Mr Varadkar's deputy, Simon Coveney, who hosted the then foreign secretary in Dublin two years ago, talked about "working constructively" to "strengthen British-Irish relations".
But alongside the two national flags in that tweet Mr Coveney included the EU flag - reinforcing the message that Ireland is part of the EU family and dispelling any potential move by Mr Johnson to apply pressure on Dublin over the backstop.
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The Irish government and EU are standing firm - the Withdrawal Agreement is not open for renegotiation and the backstop will remain.
Micheál Martin, the leader of the main opposition party Fianna Fáil, was less diplomatic about the new prime minister and questioned Mr Johnson's ability to lead the UK in these challenging times.
He said Mr Johnson, on his last visit to Dublin, failed to show the "slightest level of understanding" about the complexities of Brexit or the operation of the Good Friday Agreement.
He added that Mr Johnson's move into Downing Street raises "enormous fears" for the future of Anglo-Irish relations and British policy towards Northern Ireland.
Sinn Féin said it will stand firm against Boris Johnson's "reckless Brexit agenda" and warned that it will continue to push for a referendum on Irish unity.
The party's President Mary Lou McDonald said she had written to Mr Johnson about Brexit, the need to restore the power sharing institutions of the Good Friday Agreement and to "establish clear criteria for the calling of a referendum on Irish Unity".
"The people of the north voted to remain within the EU and that vote must be respected," she added.
While the leader of the Labour party Brendan Howlin warned that Boris Johnson may use the threat of a no-deal Brexit to panic EU leaders into re-opening the withdrawal deal.
Brexit aside, Dublin is also heavily involved in talks to restore power sharing in Belfast and it is waiting to see what impact Mr Johnson's administration will have on the process.
His opponent in the Conservative leadership race, Jeremy Hunt, pledged to get personally involved in the talks if elected, but Mr Johnson is unlikely to adopt that approach.
His focus will be elsewhere.
In the month when an Irishman led England to World Cup cricket glory and an Irish golfer lifted the Open's Claret Jug, Mr Johnson is now playing a game of high stakes for both London and Dublin.