London Olympic officials have reached an agreement to allow a female Saudi Arabian judo athlete to compete wearing a headscarf.

The International Olympic Committee says Wodjan Shaherkani can wear a hijab. The International Judo Federation had said a headscarf could be dangerous because the sport includes chokeholds and aggressive grabbing techniques.

In competition Tuesday, American Michael Phelps can become the first male swimmer to win a gold medal in the same event in three successive games when he competes in the 200-meter butterfly final.

A medal would also tie him with Soviet gymnast Larisa Latynina on the all-time list with 18 career medals.

After three days of competition, China and the United States are tied with 17 medals, followed by Japan with 11, Italy with 8 and France with 7.