British MPs voted in favour of a bill Tuesday to end Britain's EU membership, a key moment for the government's Brexit strategy despite opposition accusations of an unprecedented power grab.

Lawmakers voted by 326 to 290 in favour of backing the legislation, after more than 13 hours of debate, which will now go forward for further scrutiny by MPs.

The bill is aimed at repealing the 1972 law through which Britain joined the bloc, transferring in bulk around 12,000 existing EU regulations onto the British statute books