Labour is not going to block Brexit "in a trivial way," shadow Home Secretary Diane Abbott has said.
When she was asked whether Labour would uphold a parliamentary vote on Brexit, Ms Abbott told the BBC's Andrew Marr Show: "We're not going to block it in a trivial way. But there are really important issues for the British economy.
She added: "If we lose access to the single market, let alone the customs union, would be a huge blow to the British economy."
Pressed by BBC political editor Nick Robinson, who was standing in as host of the show, on whether Labour might block or delay Brexit under those circumstances, Ms Abbott replied: "No. Block sounds like we're being wilful.
"We will make the case or what's right for the British economy. What else would you expect us to do?"
Earlier on Sunday, John McDonnell said both Andy Burnham and Ms Abbott speak for Labour on Brexit.
Ms Abbott and Mr McDonnell said the party was in favour of a fair system to control immigration.
But both also stressed the importance of the economy during Brexit negotiations, with Ms Abbott saying freedom of movement was "inextricably linked" with access to the single market.
Ms Abbott said: "We believe in regional autonomy and Andy [Burnham] has always had those views.
"But the truth is you cannot have access to the single market without a measure of freedom of movement.
"My experiences of Labour party members all over the country want immigration rules that are fair and they want reasonable management of migration."
She added that it "would be wrong to put the economy anything other than first" as part of Brexit negotiations.
Ms Abbott also said Jeremy Corbyn would close the gap in the polls with Theresa May within the next 12 months.
She said: “I'm confident we can close the gap in the coming 12 months.
“We've had a pretty difficult 12 months, partly Jeremy's enemies in the party, partly commentators, but we have the right policies and we have the right leader.”
Earlier this week, a YouGov survey saw Labour hit a seven-year poll low, sinking to only 25 per cent — 17 points behind the Conservatives.
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