Sajid Javid warns UK citizens in northern Syria to leave within 28 days or risk ten-year prison sentence

Sajid Javid has told British citizens in northern Syria to leave within 28 days or face a ten-year prison sentence if they try to return to the UK.

The home secretary said he was also considering banning British nationals from travelling in the first place to Idlib province in north-west Syria - the last remaining territory held by rebel groups - and other areas in the north-east of the country.

Idlib, which is home to around three million people, is surrounded by Syrian government forces but is still mainly controlled by jihadist alliance Hayat Tahrir al-Sham (HTS) - previously known as the al-Nusra Front, which had links to al-Qaeda.

In a speech to security officials at Scotland Yard, Mr Javid told UK citizens in northern Syria that they are "on notice".

It is the first time he will use the powers given to the home secretary in the Counter-Terrorism and Border Security Act, which became law earlier this year. The act allows the government to ban British nationals from travelling to or remaining in specific areas. Those who fail to comply can be imprisoned for up to ten years.

The speech is likely to be seen as part of Mr Javid's campaign to succeed Theresa May as prime minister.

He said: “I’ve asked my officials to work closely with the police and intelligence agencies to urgently review the case for exercising this power in relation to Syria, with a particular focus on Idlib and the North East.

“So anyone who is in these areas without a legitimate reason should be on notice.”

He also explained how the UK is working to stop its citizens from joining Isis, saying: “The police and security services have worked tirelessly to identify those intending to travel overseas and join Daesh.

“They have seized passports at the border and prevented them from leaving the country.

“Along with concerned friends, families and public-sector colleagues, they have directed hundreds of at-risk individuals to support our Prevent programmes to turn them away from terrorism.”

Mr Javid also emphasised the need for international co-operation on security issues.

He said say: "From terrorism, to crime, to hostile state activity, we are facing international problems, and they require an international response.

“As these threats become more global we all rely on an international system of defence, policing, security and intelligence. A safety net based upon cooperation, and unity.

He added: “These structures rely upon free, democratic nations to pool information, coordinate law enforcement action, and surrender suspected criminals across borders.

“More than any other country on Earth, the UK has a coherent, connected approach to intelligence and security and when threats appear, the world still turns to the UK for leadership, support, and action.”