British Prime Minister Theresa May has suffered another humiliating defeat in Parliament after MPs voted to reject her latest Brexit plans.

On another dramatic day at Westminster, MPs voted by 303 to 258 on Friday morning (Australian time) against a motion endorsing the government’s approach to leaving the European Union.

Labour leader Jeremy Corbyn immediately called on the Prime Minister – who did not take part in the debate ahead of the vote – to “admit her Brexit strategy has failed”.

With just 43 days remaining until Britain is due to cut ties with the EU, a solid Brexit plan is no closer to finding approval.

The latest defeat came after the pro-Brexit Tory European Research Group announced it had taken a “collective decision” for its MPs to abstain.

Furious pro-Brexit MPs said supporting the motion would have amounted to an endorsement of efforts to rule out a no-deal Brexit.

Ms May’s office blamed Mr Corbyn for the defeat, saying the Opposition Leader had “yet again put partisan considerations ahead of the national interest” by voting against the government’s motion.

A prime ministerial spokesman said Ms May would continue to seek legally-binding changes to the controversial Irish backstop “insurance policy” in her deal to avoid customs checks between Northern Ireland and the Republic of Ireland.

The Prime Minister’s office earlier warned that defeat could damage Ms May’s negotiating position with Europe.

The wording of the motion called on MPs to reiterate their support for the approach set out in an earlier set of votes on January 29.

On that occasion, the Commons voted for a government-backed amendment calling on ministers to reopen negotiations with Brussels on the Northern Ireland backstop.

However, it also voted for a non-binding cross-party amendment rejecting a no-deal break with the EU.

-with AAP