Britain must put its list of Brexit demands on the table as soon as it invokes Article 50 to leave the European Union, Finance Minister Noonan has warned.
Mr Noonan spoke at the Irish Embassy in London before meeting Chancellor of the Exchequer Philip Hammond to discuss Brexit negotiations.
It came on the same day as UK Foreign Secretary Boris Johnson said that he expected Article 50 to be invoked early next year.
Mr Noonan said: "Brexit holds out a possibility of damaging the UK economy. And if it damages the UK economy, it damages the Irish economy.
"There's €1.2bn worth of goods crossing the Irish Sea every week, with 400,000 jobs depending on it, so we have common interests and I want to meet him to get an insight into the approach that the British government and he himself will adopt, after they invoke Article 50.
"Because I think there's an alignment of interests, and acknowledging the fact that we have separate interests as well, we may be able to help each other.
"Then of the course there's the whole issue of Northern Ireland, the border and the peace process and so on. So we've a lot of issues to discuss."
Mr Noonan said he had "no particular insight" into when Article 50 would be invoked and believes it is a "matter for the British government", not the Irish government.
He said: "We understand that they're not going to do it this year, but there's speculation that they may do it early next year.
"Whenever they do it, they have to be clear with our colleagues in Europe about what they want.
"If there's a long ask-list, the rest of us need to know what their priorities are, as soon as Article 50 is invoked."
The Fine Gael minister confirmed that trade tariffs and cross-border trade were points of discussion with Mr Hammond.
He said: "We think it'd be pretty ludicrous to have a hard border within 40 miles of Dublin Airport, and it would be the only land border between the UK and the EU so we want to make sure things remain pretty much are they are and people can go north and south without hindrance."
Meanwhile, Boris Johnson spoke to Sky News about the anticipated time frame for Article 50, which would trigger the process of Britain leaving the EU.
The Foreign Secretary said he expected Article 50 would be invoked in early 2017 and Britain would "take back control" with a global free trade package and a deal on financial services.
"By the early part of next year, you will see an Article 50 letter which we will invoke and in that letter I am sure we will be setting out some parameters for how we propose to take this forward," he said.
Meanwhile, in Cork, Agriculture Minister Michael Creed said Ireland will consider a special free trade zone with the UK if Brexit results in a complex UK split from the EU and the Single Market.
But he warned: "I have said repeatedly that I just don't see any upside in Brexit for Ireland."