New Delhi, April 6 -- Cameroon's parliament overwhelmingly approved a constitutional amendment to reintroduce the vice president position, a move the opposition says will further strengthen President Paul Biya's grip on power.

Biya, 93, is the world's oldest leader and has led the central African nation since 1982. He won a widely disputed election last year, his eighth term in office.

The widely criticized bill, which Biya is expected to sign into law, was approved Saturday in a joint session of the National Assembly and Senate and boycotted by the main opposition party; 200 voted in favor, 18 against and 4 abstained.

The newest amendment gives the aging president absolute authority over the office of the vice president, as he can app...