A Kenyan member of the Al-Shabaab militant group who received pilot training in the Philippines was sentenced to life in prison on Monday for conspiring to mount a 9/11-style attack in the United States.

Cholo Abdi Abdullah was convicted last year of conspiring to murder US nationals, conspiring to commit aircraft piracy and other offences.

"Cholo Abdi Abdullah was a highly trained Al-Shabaab operative who was dedicated to recreating the horrific September 11 terrorist attacks on behalf of a vicious terrorist organisation," US Attorney Jay Clayton said in a statement.

"Abdullah pursued his commercial pilot licence at a flight school in the Philippines while conducting extensive attack planning on how to hijack a commercial plane and crash it into a building in America," Clayton said.

Abdullah was arrested in the Philippines in July 2019 and extradited to the US.

According to the indictment, Abdullah attended flight school in the Philippines between 2017 and 2019 and eventually obtained his pilot's licence.

While undergoing flight training, he allegedly conducted research into methods to hijack a commercial airliner and sought information on how to obtain a US visa.

The Somalia-based Al-Shabaab was designated a "terrorist" movement by the US in 2008. (AFP)