Shannon Briggs has failed a drug test ©Getty Images

Two-time heavyweight boxing world champion Shannon Briggs has tested positive for testosterone, the World Boxing Association (WBA) have announced.

The 45-year-old's positive test was confirmed by the organisation, with the American boxer's next fight now in doubt.

Briggs is due to fight 44-year-old Puerto Rican Fres Oquendo on June 3 in Florida.

The clash would decide the vacant WBA regular title, but it could now be cancelled. 

"Heavyweight Shannon Briggs tested positive for testosterone following a Voluntary Anti-Doping Agency (VADA) test as part of the WBA Fair Boxing programme," a WBA statement read.

"Briggs, who is scheduled to fight Fres Oquendo for the WBA regular heavyweight title has the right to request the testing of the B-sample.

"WBA directors will comply with due process and respect Briggs' legitimate right to defend before ruling on it."

ESPN have claimed the test by the VADA had shown "dramatically increased levels of testosterone".

Shannon Briggs could still request that his B-sample is re-tested ©Getty Images
Shannon Briggs could still request that his B-sample is re-tested ©Getty Images

The fight against Oquendo was due to be Briggs' 69th fight of his professional career.

He has won his last nine fights since a loss to Ukraine's Vitali Klitschko in 2010, when he was comprehensively beaten while challenging for the world title.

Briggs last won a world title back in 2006, when he beat Belarus' Sergey Liakhovich.

Last November, the WBA ordered Briggs to fight Australian heavyweight Lucas Browne for the regular title.

Browne had defeated Uzbekistan's Ruslan Chagaev in March 2016, but was later stripped after he tested positive for drugs, resulting in his fight with Briggs not going ahead.