Labour's shadow Brexit secretary Sir Keir Starmer has refused to back the party's deputy leader Tom Watson over whether the UK could permanently remain in the European single market.

Sir Keir said Labour wanted the UK to secure a "changed relationship with the single market" post-Brexit despite Watson, suggesting Britain could keep its current trading arrangements with the bloc indefinitely. Starmer was speaking on the Andrew Marr show on Sunday (3 September).

The deputy leader last week told BBC Newsnight: "You have seen Keir Starmer's statement, we think that being part of the customs union and the single market is important in those transitional times because that is the way you protect jobs and the economy. And it might be a permanent outcome of the negotiations, but we have got to see how those negotiations go."

But Starmer said the transitional deal would be an interim one only. "As a short-term basis it will work," he said. "I accept the argument that we won't have votes, in fact most of the provisions that will be coming into force during that two or three year period will be provisions that we will have had a say on. But I'm not pretending transitionals are ideal, they are necessary but they should be as short as possible."

Starmer said Labour wanted the UK to secure a "changed relationship with the single market", and attempt to secure a new customs union deal with the European bloc.

This, shadow Brexit secretary said, was the party position of a "united Labour" and was a development of policy and not a U-turn. Labour had previously said Britain would leave the single market and the customs union.

No blank cheques

He said the idea the government will have negotiated a bespoke deal by March 2019 as "nonsense", adding: "What's clear now is the clock is ticking and we are going to need transitional arrangements," Starmer added. "The government at one stage was pretending we wouldn't need them.

"What we've said is the transitional period - ie from March 2019 until we get to a new and final deal - will be within a customs union and within the single market ... Labour has never said anything other than it wants to retain the benefits of the customs union and single market."

During the interview, Starmer said Labour was not out to "frustrate" Brexit over its opposition to elements of the Great Repeal Bill set for its second reading this week that will copy around 19,000 EU laws into Britain's legislation, as well as repealing the act that took Britain into the EU in 1973.

But he added Labour was about "not giving the government a blank cheque to pass powers into the hands of ministers."

"The idea of converting EU law into our law is right but the way the government has gone about it is completely wrong," Starmer added.

At least half a dozen Conservative MPs are believed to be considering joining opposition parties and rebelling to block the bill amid concerns about handing new powers to ministers.