As to nationalism, it is not for me to say someone cannot aspire to a united Ireland but I can challenge the methods they use to pursue it.
Talks aimed at propping up Mrs May's minority Government - after a disastrous General Election showing saw the Tories lose their parliamentary majority - are "ongoing", according to Downing Street sources who insisted the PM had never set a timeline on the negotiations.
"We made the case to her that we would oppose any deal that undermined the Good Friday Agreement", he said.
"As a UK Government we remain absolutely steadfast in our commitment to the Belfast Agreement (and) its successor agreements".
"From all the parties there was a sense of can do, of positivity, while at the same time having firm and clear positions, as you would expect", he said.
Mr Coveney pledged to "spare no effort" to help get the Stormont power-sharing Executive back up and running.
The comments were seen as a coded reference to the party's opposition to scrapping the "triple lock" on pensions and means testing the winter fuel allowance - both of which were in the Conservative manifesto.
The Taoiseach is likely to encourage the Democratic Unionist Party and Sinn Féin delegations to sort out the row on power-sharing.
Labour's shadow chancellor John McDonnell has raised concerns over reports the DUP want to end airport tax on visitors to Northern Ireland - which generated around £90m in 2015/16, according to HMRC estimates.
The UK Government has warned that direct rule from London could be reimposed if the local parties fail to reach an agreement before the June 29 deadline.
Mr Varadkar said that restoring powersharing was particularly important with the start of the formal Brexit negotiations in Brussels.
The border between Northern Ireland, which is part of the United Kingdom, and the Republic of Ireland, an European Union member, will become the only land border between the UK and the European Union after Britain exits the bloc in March 2019.
I may have worked in many cultures and countries in the interest of our country, but in Parliament I'm still new. "It takes two to tango and we're ready to dance".
"Not only do a huge majority of people in Northern Ireland want to see abortion made available to women and girls in the tragic circumstances of sexual crime or fatal foetal diagnosis, but they also want to see abortion decriminalised and dealt with through healthcare policy".