Andrew Lansley was forced to appear before MPs today amid Labour claims that the Government is split over its NHS shake-up.
The Health Secretary had to cancel a speech to local government leaders after Commons Speaker John Bercow granted an urgent question.
Shadow health secretary Andy Burnham was demanding answers after Nick Clegg backed further changes to the Health and Social Care Bill in a joint letter with Baroness Williams.
Mr Clegg insisted the "final changes" would appease Lib-Dem anger, but Downing Street insisted there would be no "significant" amendments.
Mr Lansley defended the reforms and said he had always been willing to offer reassurances.
Earlier, health minister Simon Burns said the Government was not "giving in" to Lib-Dem demands.
