George Osborne has vowed to push on with plans to reform tax credits despite Monday night's defeat in the House of Lords.
The Chancellor told the House of Commons he would unveil his new plan in next month's Autumn Statement.
He also criticised the Lords for voting down the plans, saying it raised "constitutional issues".
"We will continue to reform tax credits and save the money needed so that Britain lives within its means, while at the same time lessening the impact on families during the transition," Mr Osborne told MPs.
There were further calls for the plans to be scrapped during Treasury questions, with Labour MP Wes Streeting saying the Chancellor was "manufacturing a phoney constitutional crisis" rather than going "back to the drawing board".
Shadow Chancellor John McDonnell said Labour would not attack the Government if the plans were reversed "fairly", calling for Mr Osborne to "listen to reason".
They are not there to interfere with the settled will of the House of Commons, warned Boris Johnson.
A working mum who would be hit by Tax Credit cuts spoke to ITV News ahead of the House of Lords vote on the changes.
Peers will have to decide whether to delay changes to the tax credits bill, review them or scrap it altogether.