The New Zealand Rugby Union launched a major anti-corruption drive on Wednesday, demanding that thousands of top-level players and administrators sign a pledge to keep the game clean.

After a string of match-fixing and other corruption scandals in professional sports around the world, the union's general manager said it was vital to protect rugby's integrity and to keep the reigning world champions free of graft.

Around 2,000 players, coaches and managers involved in New Zealand rugby at a professional level are being asked to sign a pledge to abide by new regulations. All are banned from betting on rugby matches no matter where in the world they are played.