The England National Game XI looks set to be joined by teams from Wales, Ireland and Northern Ireland in next season's European Challenge Trophy.
Plans are under way for the competition, which was won by England's under-23 non-league side last month, to be expanded to an eight-team event.
Wales, Ireland and Northern Ireland have expressed an interest in joining England, Italy, Holland and Belgium in the competition, which would be played in two groups of four with a one-off final in the spring of 2009 and play-off matches for the other positions.
The FA's Leagues Manager Mike Appleby said: "The two Irish Associations and the FAW agreed to confirm their participation by the end of March next year. We also have a few options to explore with regard to the eighth team."
The Uefa sanctioned competition, which will be re-named The International Challenge Trophy, is due to get under way in November 2007.
It will remain an under-23 tournament but players who start the tournament meeting the age criteria will remain eligible through to the final.
It is planned to hold the draw in Scotland during the Four Nations Tournament in May next year.