The British Olympic Association will authorise its athletes to wear anti-pollution masks if they feel they are necessary during the Olympic Games in Beijing in August.

Officials in the United States, Australia and Canada have indicated that their athletes will not be using masks during competition.

But BOA chief executive Simon Clegg refused to rule out a move that would be extremely embarrassing for China.

"This is a competitive issue," Clegg told The Times newspaper. "We are in the business of trying to win medals here and beat our competitors.

"We are all hopeful that the Chinese authorities will have addressed this issue by August so the athletes are not put in a position where the measures we have put in place have to be deployed.

"But we are in the business of providing our athletes with competitive advantage. We need to put in place whatever strategies are appropriate to ensure that we give our athletes the best chance of delivering."

Beijing's mayor, Guo Jinlong, admitted last month that the sprawling, traffic-choked city faced a massive task in trying to bring pollution down to bearable levels in time for the Games.

The International Olympic Committee has warned that endurance events such as the marathon could be postponed or cancelled to protect competitors if air-quality standards are not met.

AFP