Detained Ugandan opposition politician Kizza Besigye has begun a hunger strike as his time spent in detention awaiting trial nears three months.

Besigye, 68, was charged in a military court with possession of pistols and attempting to purchase weapons abroad - accusations which he denies.

On Tuesday, an aide from Besigye's political movement, the People's Front for Freedom (PFF), told the BBC: "We believe he is protesting because he should not still be in prison - he should be home."

Besigye's trial was initially postponed until January - it is now unclear when the court case will begin.

Besigye used to be a personal doctor for Uganda's longtime president, Yoweri Museveni but went on to become an opposition leader.

He has contested and lost four presidential elections against Museveni, who has been in power since 1986. The veteran opposition figure has previously accused the Ugandan authorities of political persecution.

He has been less active in politics in recent years and did not contest the 2021 election.

However, Besigye returned to the headlines last month after he was dramatically abducted while visiting Kenya and forcibly taken to Uganda.

The detention sparked widespread condemnation and fears of a clandestine exchange of intelligence between the two neighbours.

Besigye was then charged along with an aide, Obeid Lutale. Mr Lutale also denied the charges.

In a landmark ruling last month, Uganda's Supreme Court declared it unconstitutional for military courts to try civilians, ordering the transfer of all such cases to civilian courts.

The move angered President Museveni, who dismissed it as "a wrong decision" and vowed to challenge the ruling.

Besigye has had various other run-ins with the law.

On Tuesday, the opposition politician was expected to appear before a civilian court for a hearing on a 2022 case in which he is accused of holding an unlawful demonstration. However, he did not attend the hearing, citing health reasons.

In 2005, Besigye was arrested while returning from a political rally ahead of the 2006 presidential polls and charged with treason. The charges were thrown out by the courts.

He was also charged with rape in a separate case. The charges were later dropped. He said all the allegations were part of a campaign of political persecution.

Museveni has defended the use of military courts to try civilians.

He said any crime involving a gun was dealt with in a military court to ensure the country's stability as civilian courts took too long to deal with cases.

Opposition parties have frequently complained about restrictions on political activities, alleging that Museveni fears political competition.

Museveni's supporters deny the allegation and say he has maintained stability during his rule of almost 40 years.