Uganda's President Yoweri Museveni on Monday signed a new law allowing civilians to be tried in military courts that critics said could be used against opposition leaders ahead of next year's election.

The new law comes despite a ruling by the Supreme Court in late January that it was unconstitutional for civilians to be tried in military courts as was the case for opposition leader Kizza Besigye.

Besigye, 69, was abducted by armed men in Nairobi in November and re-emerged a few days later at a military court in Uganda, where he was charged with treason, which carries a potential death penalty.

Following the Supreme Court ruling, his case was moved to a civilian court.

'Exceptional circumstances'

But the new law provides for "exceptional circumstances" under which civilians can be subjected to military law, including the "unlawful possession of arms, ammunition or equipment," one of the other charges Besigye is facing.

The signing of the law was announced by Uganda's parliament on X.

Besigye's lawyer Erias Lukwago told AFP the law was designed to facilitate the "illegal detention and trial of Besigye and others."

Besigye has been in jail for more than the six-month legal limit for detention without trial.

Opposition 'being targeted': Bobi Wine

Uganda's other major opposition leader, Bobi Wine whose real name is Robert Kyagulanyi, told AFP: "All of us in the opposition are being targeted by the Act."

Human rights lawyer and activist Eron Kiiza – who was jailed by a military court for six months for alleged misconduct while defending Besigye – said he will legally "challenge the Act."

Rights groups say Besigye's abduction and trial for treason are linked to the election in January, when Museveni, 80, will seek to extend his 40 years in power.