UK will press ahead with Brexit laws despite lack of consent from Scotland - minister

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LONDON, June 14 (Reuters) - The government will press ahead with passing legislation to end Britain's membership of the European Union despite the devolved Scottish parliament not having granted its consent, Secretary of State for Scotland David Mundell said on Thursday.

Differences over Brexit have strained relations between the United Kingdom's four nations. Scotland and Northern Ireland voted to stay in the EU in a 2016 referendum, while Wales and England vote to leave.

Under a constitutional mechanism known as the Sewel Convention, the British parliament must seek consent from the Scottish parliament when it makes laws that have an impact on policy areas that are devolved to the Scottish government.

Scotland has so far withheld its consent. But Mundell said on Thursday that the convention did not apply in unusual circumstances like Brexit and could not impede the passage of the European Union (Withdrawal) Bill.

"We on this side of the house have compromised, we have made every effort to reach agreement. We have sought consent," Mundell told parliament.

"Now (Frankfurt: 11N.F - news) , we are legislating in line with the Sewel Convention to ensure the whole of the United Kingdom leaves the EU with as much legal certainty as possible. That's what people and businesses in Scotland need."

The Scottish government has so far rejected the London's plan for Brexit, saying it amounts to a power grab that will see policymaking powers taken back from the Scottish parliament indefinitely.

The government has rejected that argument, saying its plan contains a promise to hand all existing powers back to Scotland when it can, and to expand the areas under Scottish control.

"It is incumbent on this government to deliver Brexit and this is what we will do ... The situation is that the government will seek consent unless there are not normal circumstances ... I think everybody would accept that the UK leaving the EU are not normal circumstances," Mundell said. (Reporting by William James and Elizabeth Piper,)