British police say a London teenager has been charged with preparing acts of terrorism.

The Metropolitan Police force says 19-year-old Haroon Ali-Syed is accused of engaging in "conduct in preparation" of terrorist acts between April and September.

Ali-Syed was arrested at his home in west London on Thursday. Two other men, aged 19 and 20, detained at the same time have been released on bail.

Police have not given details of the allegations against Ali-Syed, but said his arrest was part of an "intelligence-led investigation" by counterterrorism officers.

He is due to appear in court Tuesday afternoon.