Shadow home secretary Diane Abbott repeatedly declined to spell out her position on the deportation of illegal immigrants as she was pressed on the issue eight times in a live TV interview.
Ms Abbott told ITV1's Good Morning Britain she did not back an amnesty of the kind floated by Boris Johnson and said it was "not Labour's position" that up to a million people believed to be living illegally in the UK should be made to go home.
But when presenter Piers Morgan pressed her for more detail, the shadow home secretary said only that she was working on a policy which would make the handling of migration "fairer and more efficient".
Ms Abbott said: "The immigration and nationality department is not fit for purpose. That's why many of these issues have arisen. I don't blame the staff, but it is an department that needs reviewing and reorganising and the right level of support.
"We are working on immigration policy. Obviously, post-Brexit everybody has got to consider immigration policy. But the main plank of what we want to do is have a much fairer system - fair rules and a reasonable management of migration."
She suggested that viewers would be "surprised" that Morgan did not want to discuss the Windrush scandal.
But the presenter said they had already spent some time talking about that issue, telling Ms Abbott: "I'm not trying to trap you, I'm just trying to ask you a simple question.
"What do we do about illegal immigrants in this country? Do we let them stay? Boris Johnson has suggested an amnesty, you say no amnesty, so the logical fallout from that is that we get them all out of the country, isn't it?"
The pair continued their spat later on Twitter, with Ms Abbott saying that viewers would judge for themselves whether Morgan was trying to trap her.
Morgan insisted he was not, and accused the shadow home secretary of failing to give "a straight factual answer to this fundamental question".