Taoiseach Leo Varadkar has said the Government does not want any sort of economic border on the island of Ireland after Brexit.
Mr Varadkar said if Britain wants to put forward technological solutions that is up to them, but the Government would not do that work for them.
In what is the most hard-hitting response yet from the Taoiseach on the issue of the border, he said the Government was not going to design a border for the Brexiteers.
"So let them forward their proposals as to how they think a border should operate and we'll ask them if they really think this is such a good idea," he said.
He warned that it would have a very severe impact on the British economy "if they go down that route".
The Taoiseach said he hoped there would not be an angry response from unionists to the Government's position.
"It is the British and the Brexiteers who are leaving, so if anyone should be angry it's us quite frankly.
"But we are not going to get angry. We are going to try and find solutions or at least minimise the damage to relations between Britain and Ireland, to the peace process and to trading links," he said.
He said both he and Minister for Foreign Affairs Simon Coveney are in agreement on the issue.
Brexit border issue requires 'imaginative solutions'
Earlier, Mr Coveney said Ireland cannot support proposals resulting in border checkpoints between Northern Ireland and the Republic.
The Department of Foreign Affairs reiterated that the Government's position on the issue of the border in Brexit negotiations is a political not a technical matter.
In a statement, it said avoiding a hard border after Brexit will require "flexible and imaginative solutions".
The statement followed a report in the Times newspaper that the Government is pushing for the Irish Sea to become the post Brexit border with the UK.
The newspaper reported that the Taoiseach was unconvinced by the UK's plans to introduce a hi-tech land border between Northern Ireland and the Republic after Brexit.
The border between Northern Ireland and the Republic is one of the key issues that needs to be resolved by the UK and the EU before talks begin on a new trade deal.
British ministers had proposed using measures such as surveillance cameras to allow free movement between the north and south.
However, sources told The Times that Mr Varadkar thinks these plans could jeopardise the peace process and restrict movement between the two countries.
Speaking on RTÉ's News at One, Minister Coveney said Britain has chosen to leave the EU and there is an onus on it to make sure the consequences of that decision do not harm Ireland.
He said: "We have a border that is 500km long. There are 400 road crossings along that border.
"Anybody who suggests to me that we can solve this problem by putting cameras on this border ... I don't think that is the approach we can take."
The DUP, needed by British Prime Minister Theresa May to prop up her minority administration in the House of Commons, has ruled out the suggestion of a sea border post Brexit.
DUP chief whip Jeffrey Donaldson said: "There is no way that the DUP would go for an option that creates a border between one part of the United Kingdom and the other."
He told BBC Radio 4's Today programme: "Dublin really needs to understand that that proposition is absurd and unconstitutional."
DUP MP Ian Paisley said the reported position of the Irish Government appeared to leave two alternatives - a "very hard border" or that "Ireland will wise up and leave the EU" itself.
Meanwhile, a post-Brexit transitional period is expected to be completed within three years of the UK leaving the European Union, the British Chancellor has said.
Philip Hammond said there was a "broad consensus" that the "treaty-based arrangements" with the EU would be in force by the next scheduled general election in June 2022.
But Mr Hammond said on the first day after leaving the bloc in March 2019 "many things will look similar".
Ulster Unionist Party leader Robin Swann described the Taoiseach's language over the border issue as totally irresponsible.
Mr Swann said if the Taoiseach thinks he is going to use the border to make a name for himself, he should think again.
He said if the Government continues to harden its language in relation the border then it is showing total disrespect to the people of Northern Ireland and their right to self determination.