The deal comes after six months of protracted negotiations and a final five-hour meeting in Brussels on Monday.

The agreement will create one main transfer window per season and a new compensation framework to reward the "training effort" of smaller clubs.

There is also provision for sporting sanctions and financial punishment for unilateral breaches of contracts.

The new rules governing cross-border transfers should be in place for next season once Fifa's executive approves the changes at a meeting in Buenos Aires on 5 July.

Fifa president Sepp Blatter announced the deal alongside Uefa president Lennart Johansson and European Commissioners Mario Monti (responsible for competition), Viviane Reding (sport), and Anna Diamantopoulou (social affairs).

He declared: "It will be for the protection of the young players, training clubs and the fans.

"They will have footballers which are protected by contract but they will also have clubs which will have at their disposal footballers for a certain time."

Johannsson added: "I think this is a good result for European football."

And commissioner Reding said: "Football comes out stronger than it was before. I believe it is a great night for football and for European sport."

Players' union angry

Initial discussions were prompted last autumn by the EC's assertion that the current system, where clubs demand a fee for in-contract players, broke EU employment rules.

The EU executive had warned it could impose its own regulations, raising fears that the game could face its biggest shake-up since the 1995 Bosman ruling outlawing transfer fees for out-of-contract players.

European players union Fifpro wanted far more lenient conditions for players and withdrew from final negotiations.

Spokesman Laurent Dennis condemned Monday's deal and hinted at a legal challenge.

"It's a very black day for European sport and footballers," he insisted.

Blatter acknowledged there were still hurdles to overcome, specifically with regard to acheiving consensus with other bodies.

"We will have to continue the dialogue with the players' unions in order to make sure that the whole football family is joined and we will work for the benefit of those who practice and watch the game," Blatter said.