A Sri Lankan court has rejected an appeal by the country's former army chief and opposition leader.

The unanimous decision Friday upholds Sarath Fonseka's conviction and 30-month prison sentence for arms procurement offenses. The former general is also serving a three-year sentence for making false allegations about the defense secretary in a 2009 newspaper interview, a conviction that cost him his parliamentary seat.

Fonseka says the cases against him are politically motivated because he challenged President Mahinda Rajapaksa in the presidential election.

Fonseka is widely credited with defeating Tamil Tiger rebels in May 2009 after the 25-year civil war. Both Fonseka and President Rajapaksa were hailed as heroes by Sir Lanka's majority Sinhalese, but the two men soon parted ways over political ideology.

Fonseka then quit the army and made his unsuccessful run for the country's presidency.