London, Jun 3 (IANS): The UK faces a severe threat from Islamist terrorism for at least another two years and the danger could increase further, the Home Office has said.

"In summary, we expect the threat from Islamist terrorism to remain at its current, heightened level for at least the next two years, and that it may increase further," the Guardian quoted the Office as saying on Saturday.

"We assess the threat from extreme rightwing terrorism is growing.

"Globally, terrorist groups and networks of all ideologies continue to develop organically, exploiting social media, technology and science to further their aims and ambitions."

The assessments emerged as the government prepares to unveil a strengthened counter-terrorism strategy.

On Monday, Home Secretary Sajid Javid will announce a range of steps aimed at boosting the authorities' efforts to stop atrocities.

Security agencies and counter-terror policing have foiled 12 Islamist and four extreme rightwing plots since March last year.

MI5 and the police are running more than 500 live operations involving roughly 3,000 "subjects of interest".