Gabon's opposition leader Mike Jocktane Sunday said police tried to detain him as he was driving through Libreville, adding that his driver managed to lose his pursuers.

Jocktane is currently on trial on what he says are trumped up charges of disrupting public order, during a 2011 protest he denies even attending.

"We were in a car and a white pick-up truck drew up with us. They said they were policemen and asked that I follow them. As it was a Sunday, we refused and left. Two cars then tried to chase us. We escaped," Jocktane told AFP.

His driver confirmed the story and admitted to knocking a French embassy vehicle during the chase.

Police could immediately be reached for confirmation.

Jocktane, a former aide to president Omar Bongo, who died in 2009 after 42 years at the helm of the oil-rich former French colony, claimed in a book on France's African networks published in November that Bongo helped finance French President Nicolas Sarkozy's victorious 2007 campaign.

The opposition leader, who founded his own charismatic church years ago, also faces charges of bringing the country into disrepute because of his book.