The prime minister has insisted the government will make a “significant contribution” to the redevelopment of Casement Park.
Rishi Sunak refused to say how much more money the government would be willing to put up or if it would happen in time for Euro 2028.
He was asked about the issue by BBC News NI during a visit to Belfast on Friday.
The PM also said ongoing discussions meant he would not say when exactly the government will make further details public.
However, he added he would ensure there would be a “great legacy for Northern Ireland” in the Euros.
Northern Ireland is due to host five games in the football championships at Casement Park in west Belfast.
But the stadium site remains derelict and redevelopment work has yet to begin.
At the weekend, the Irish FA and the GAA sent a joint letter to the prime minister urging him to clarify the funding for the project.
But the cost of the redevelopment could be more than £300m and the PM would not say whether funding will be confirmed before July’s general election.
Conservatives record in Northern Ireland
During his visit to Belfast Mr Sunak also defended his party’s record in government and said the Conservatives had a track record in delivering for Northern Ireland.
He denied his visit was just a tick-box exercise, even though the party does not stand many candidates in Northern Ireland and said he cared “deeply” about the union.
The PM visited an advanced maritime manufacturing facility in Belfast’s Titanic Quarter, where he spoke to apprentices and rode on a small zero-emission electric boat.
The boat has been manufactured by Artemis Technologies, a company that has received government funding to support its work.
Mr Sunak was accompanied by Northern Ireland Secretary Chris Heaton-Harris, as he spoke to staff and participated in some of the manufacturing processes.
Analysis: Brendan Hughes, political reporter
Prime Minister Rishi Sunak’s visit to Northern Ireland will be fleeting, not least because Tory electoral prospects across the Irish Sea are few and far between.
While the Conservatives do stand some candidates in Northern Ireland, they have little electoral success.
In the last general election the party ran four candidates in Northern Ireland and secured less than 1% of the vote.
The Labour Party has had a longstanding policy of not contesting elections in Northern Ireland, and the Liberal Democrats do not field candidates either.
Reform UK announced in March a partnership with local party Traditional Unionist Voice (TUV), which was expected to involve fielding joint candidates.
But blaming delays in processing paperwork, Reform UK confirmed on Thursday it will not have candidates in Northern Ireland and will instead endorse the TUV.