Following talks between Irish Taoiseach Enda Kenny and David Cameron, the British Prime Minister said the two governments are determined to go “further and faster” in deepening relations.
“We are not letting our foot off the pedals; we want to go further and faster with this relationship and we have tasked our teams to identify more we can do to strengthen collaboration in specific sectors to boost growth,” he said.
Both leaders said they had instructed top civil servants to work up policy.
After the meeting, the pair went to the House of Commons for what the Prime Minister called “a small St Patrick’s Day celebration”.
The Taoiseach joked that he had handed over “the key” to beating Wales at rugby - ahead of the Six Nations decider with England in Cardiff.
Ireland are the only team to have beaten Wales in this year’s tournament so far.
“I’ll make sure I pass it on,” Mr Cameron quipped back.
Earlier in an address to the London School of Economics later, Mr Kenny said Ireland and Britain had travelled a long distance together within the EU.
“The UK is an enormously important partner for us in Europe,” the Taoiseach said.
“We greatly value the contribution you make, and we look forward to it continuing long into the future. It is good for Europe, good for Ireland and, not least, good for the UK.”