assurances from Fifa
, the nations are concerned that selection of their players will undermine their independent status in the international game.
The 18-strong men's squads must contain 15 players who were born on, or after, 1 January 1989 - but three players can be older. There are no age limits for the women's selections.
But Pearce, the England Under-21 manager since 2007, added: "A lot of it will depend on the players' mentality. If the players want to be part of it, that would be fantastic. I think they will.
"I think they will be very, very excited to be part of this showcase of football.
"Dialogue will come into it between myself, the federations, and the managers concerned. I think support will be galvanised as the months go by and the tournament nears kick-off."
But former Scotland manager Craig Brown doesn't want Scottish players to play.
Gordon FarquharBBC Sports News correspondent
“Team GB's new football coaches are guilty of wishful thinking if they believe they will be able to pick freely from the home nations. The Welsh, Scottish and Northern Irish FAs have become weary of repeating their opposition to a GB team. Stuart Pearce and Hope Powell must hope individuals are so driven to play that they are prepared to take a defiant stand ”
He told BBC Radio 5 live: "I wish them every success but I would still be disappointed if any selected Scottish player took part.
"We fear the autonomy of Scottish football would be jeopardised if we were to play and it would be selfish of the player."
Pearce said he would only select players on "form and fitness" - and refused to be drawn on whether Beckham will be included.
"I've not seen him play recently, he's a bit old for the Under-21s," Pearce joked.
"I was fortunate to be part of Euro 96, so I know how special it can be to play for your country on home soil at a major tournament.
"I'm sure this group of players will relish being part of not only a huge tournament in this country, but a unique one competing together and representing the UK."
Powell has led England's women for 13 years, including four successive major finals, including Euro 2005 on home soil.
She said: "The attendances at the games during Euro 2005 were a sign of progress for women's football in this country. It helped provide a platform for what has happened since then.
"I'm delighted to be in the position to be able to take a team into such an illustrious tournament, I just wish it were starting tomorrow."
The Football Association made the appointments after being instructed by the British Olympic Association to oversee Team GB.
FA boss David Bernstein sympathetic over Team GB concerns
FA chairman David Bernstein said: "With their excellent track record and experience I am convinced we have chosen the best coaches for these positions."
Britain will field a men's team for the first time since the Rome Games of 1960, while the women are making their debut.
But a Scottish FA spokesperson said supporters agreed with their stance.
"We have been consistently clear in our position and, in particular, the threat it poses to our independent membership of FIFA and also our representation on the International Football Association Board," the spokesman said.
"It is imperative we preserve our voice at the top table of world football and the supporters are in agreement with our stance.
"We have consulted with the men's and women's international squads in order that they understand our position, the reasons for that position and are aware of the feelings of the supporters."
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