Guto Bebb's resignation comes after MPs voted 305 to 302 in favour of a pro-Brexit lawmakers' amendment to the customs legislation.
British junior defence minister Guto Bebb resigned on Monday after voting against a government-backed amendment on the customs bill put forward by pro-Brexit lawmakers, according to reports.
Bebb, minister for defence procurement, voted against the amendment that will stop Britain collecting tariffs for the European Union after Brexit unless there is a reciprocal arrangement.
The amendment was narrowly approved by parliament, in a vote of 305 to 304, with the government's support.
He confirmed to the BBC that he had resigned from government following the vote.