WASHINGTON (REUTERS) - President Donald Trump has ordered the withdrawal of most American troops from Somalia, the Pentagon said on Friday (Dec 4), part of a global pullback by the Republican president before he leaves office next month that will also see him drawdown forces in Afghanistan and Iraq.

The United States has about 700 troops in Somalia focused on helping local forces defeat the Al-Qaeda-linked Al-Shabaab insurgency.

The mission has received little attention in the United States, but has been considered a cornerstone of the Pentagon's global efforts to combat Al-Qaeda.

In a statement, the Pentagon sought to play down the implications of a withdrawal that experts have said could undermine security in Somalia.

"While a change in force posture, this action is not a change in US policy," the Pentagon said.

"The US will retain the capability to conduct targeted counterterrorism operations in Somalia, and collect early warnings and indicators regarding threats to the homeland."

The United States already pulled out of Somalia's cities of Bossaso and Galkayo earlier this year.

As of last month, US troops were still in the southern port city of Kismayo, Baledogle airbase in the Lower Shabelle region, and in the capital Mogadishu.

The Pentagon statement, which was unsigned, said an unspecified number of forces in Somalia would be moved to neighbouring countries, allowing them to carry out cross-border operations, it said.

Others would be reassigned outside East Africa.

Somalia has been riven by civil war since the early 1990s, but over the past decade an African Union-backed peacekeeping force and US troops have clawed back control of Mogadishu and large swathes of the country from Al-Shabaab.

A US defence official, speaking on condition of anonymity, said those US troops remaining in Somalia would be based in the capital.

It is the third major withdrawal since Trump installed acting Defence Secretary Christopher Miller, a former Green Beret and counterterrorism official, at the Pentagon after losing the presidential election to Democrat Joe Biden.

The US defence official said the withdrawal was ordered to be completed by Jan 15 - the same deadlines for drawdowns in Afghanistan and Iraq.