A mass meeting of NRL players on Monday may vote to boycott this year's World Cup as the RLPA increases pressure, despite the NRL's 16 clubs unanimously agreeing last week to grant them an effective 52 per cent pay increase.

A proposal to ask NRL players, who will fill key positions in World Cup teams over the five-week tournament beginning late October, to withdraw their services was tabled at an executive meeting of the RLPA on Sunday and will be raised at the mass meeting of 300 players in Sydney.

NRL clubs, however, claim such a player boycott would be in breach of their contractual obligations to promote the code.

They point out that, unlike the Australian Cricketers' Association, whose players were out of contract when they cancelled one tour and threatened to boycott another, 87 per cent of NRL players are already signed to contracts from November 1.