By Justin Huggler in Berlin

3:59PM GMT 13 Jan 2016

Angela Merkel is facing a fresh rebellion over her refugee policy, with more than 40 politicians from her Christian Democrat party reportedly signing a petition to close Germany's borders to asylum seekers.

The rebels plan to call for a vote on the proposal at the next party meeting on January 26.

Mrs Merkel has come under intense pressure to change her “open-door” refugee policy since it emerged that asylum seekers were among the suspects in the New Year’s Eve sex attacks in Cologne.

More than 650 women have now come forward to file criminal complaints over the attacks, around 45 per cent of them for sexual assault.