Women's 400 metres world champion Salwa Eid Naser of Bahrain has been handed a provisional suspension for failing to make herself available for anti-doping tests, the Athletics Integrity Unit (AIU) said on Friday.

Naser won gold at the World Championships in Doha last year with a time of 48.14 seconds, the third fastest in history, to become the first Asian to claim the women's 400 metres world title.

"The AIU has provisionally suspended Salwa Eid Naser of Bahrain for whereabouts failures, a violation of the World Athletics Anti-Doping Rules," the AIU said in a statement.

Naser, 22, was born in Nigeria before switching her allegiance to Bahrain in 2014.

According to World Athletics Anti-Doping Rules, any combination of three missed tests or filing failures within a 12-month period by an athlete constitutes a whereabouts failure violation.

Athletes could face two-year bans or a minimum of one year depending on the degree of fault.