Jeremy Corbyn may have only decided to genuinely support the UK's membership of the European Union in the last few weeks, a shadow cabinet minister has said.
The Labour leader voted against Europe in the 1975 referendum and has faced accusations he has not been campaigning forcefully enough for a 'Remain' vote at the referendum in June.
Asked on BBC Question Time last how genuine Corbyn's "new found support" for the EU was on a scale of one to ten, Owen Smith said he thought it was "about a seven".
"Jeremy is someone who used to be opposed to the EU, very clearly he voted against it the 1970s," the shadow work and pensions secretary acknowledged.
"In the last few years and perhaps even in the last few weeks he has come to a different view and a view which is now I think united with the Labour movement we now feel collectively we should stay in the EU."
Smith added Corbyn's claim to now back EU membership was perhaps "not a ten" on the scale.
"He, like many of us, has thought hard about whether he should be 'In' or 'Out' and he has decided on balance we should be 'In'," Smith said.
Yesterday Corbyn gave his first major speech on the EU referendum and insisted there was "nothing half-hearted" about his campaign.
On Wednesday, former shadow chancellor Chris Leslie said that Corbyn had to be more vocal and passionate in supporting the In campaign.
“He says that he wants us to stay in the European Union. I believe that. But I think that he’s got to give the impression that it is absolutely what he believes,” Leslie said.
In his pro-EU speech in central-London, Corbyn said there remained serious "shortcomings" that needed to be addressed by Brussels, such as the proposed trade deal with the US which gave “huge cause for concern” about the potential for privatisation of public services, he warned.
All of those could be better dealt with, however, by remaining in the EU “warts and all” rather than by pulling out and leaving the country at the mercy of the Conservatives, he argued.
"We have had a very big debate within the party and within the trade unions. Overwhelmingly, the Labour Party and the trade unions have come to the view that they want to campaign for a social, just Europe to protect the workers’ rights that we’ve got, to extend them and extend that degree of justice."
Also appearing on BBC Question Time, Conservative MEP Daniel Hannan said Corbyn scored "about two" on the scale of how "genuine" his belief in the union was. "For poetical reasons he has to find a way of justifying switching to a pro-EU position," he said.