BOGOTA - Men's doubles world No 1 Robert Farah withdrew from this month's Australian Open on Tuesday after a positive doping test.

The 32-year-old Colombian said he was informed by the International Tennis Federation (ITF) that he was found to have traces of anabolic steroid Boldenona in a test sample provided in October.

"I will not be able to play at the Australian Open, an event for which I had been preparing since December," Farah said on Twitter.

"A few hours ago the ITF informed me of the presence of Boldenona in a test that I did on Oct 17, 2019 in Cali. Two weeks before the mentioned test ... I did an anti-doping test in Shanghai which had a negative result. And I was also tested at least 15 other times randomly in the international circuit throughout the year with the same negative result.

"As stated by the Colombian Olympic Committee in 2018, this substance is found frequently in Colombian meat and may affect athletes' test results."

Farah added: "I am calm and confident in the results of this process since I have always acted correctly and honestly in my life. I will work harder than ever to return to the courts in the shortest time possible."

The Australian Open, the first of the year's four Grand Slam tennis events, starts in Melbourne on Monday.

Canada-born Farah, who had already pulled out of this week's Adelaide International, won last year's Wimbledon and US Open men's doubles titles alongside compatriot Juan Sebastian Cabal.

Cabal, 33, is expected to contest the Australian Open doubles with another partner, according to local officials.