Shadow chancellor John McDonnell has said the Labour party will not make "political capital" from a U-turn on tax credits.
McDonnell said the issue was becoming "above politics" and revealed he has written to chancellor George Osborne to say that a U-turn is needed, but that Labour would not use it for political point scoring.
Osborne is facing increasing pressure to U-turn on proposals to cut tax credits, even from within his own party. Despite the bill passing through the Commons last week, it faces being blocked by peers in the House of Lords in an unprecedented vote on Monday.
Scottish Conservative leader Ruth Davidson is the latest Tory to warn of the impact of cuts on families. "It's not acceptable. The aim is sound, but we can't have people suffering on the way," she told the Mail on Sunday.
Speaking on the BBC's Andrew Marr Show, McDonnell said:
"If the Lords do throw this out tomorrow and put it back to the government, [if he] brings back a policy in which people are protected - not a political stunt- but a real protection, we will not in any way attack you for that - in fact we'll support you."
Speaking on the same show, education secretary Nicky Morgan warned peers they should be "very mindful of what they are doing".
I think this is constitutionally unprecedented to strike down a statutory instrument on a taxation and spending matter.