Uganda said on Monday it had begun withdrawing its troops from Somalia as part of a phased drawdown that will end an almost two-decade deployment helping Mogadishu fight the Al Qaeda-linked Al Shabaab terrorist group.

Ugandan troops were first deployed to Somalia in 2007 under the banner of an African Union mission presently known as the AU Support and Stabilization Mission in Somalia, or AUSSOM.

The first troops to leave are those deployed under the bilateral arrangement, Uganda People's Defence Forces (UPDF) spokesperson Chris Magezi said in a statement.

Uganda will gradually withdraw all its forces from Somalia, including those serving under AUSSOM, by the end of 2027, he said.

"UPDF has embarked on the drawdown of troops deployed in Somalia under bilateral arrangements with (Somalia's) Federal Government, effective immediately," Magezi said, adding that the first cohort had already returned home.

Uganda has about 4,500 troops deployed in Somalia, according to state media, though it is unclear how many additional forces are deployed under a separate bilateral arrangement.

Ali Omar, Somali state minister for foreign affairs, told Reuters: “Things are not dire now, but it could create problems if their troops suddenly pull out”.

Al Shabaab, which has waged a campaign of terror against the Somali government for about two decades, frequently targets security forces, officials, and civilians.