The care of emergency patients should be put ahead of the fight over pay and work conditions, says the NHS Employers CEO as the first all-out junior doctors strikes in history began.
Danny Mortimer, head of the organisation that is the "voice of the NHS employers", said he hoped junior doctors could "step back from this action going forward".
Mr Mortimer also added the employers he represents would "urge doctors to step back from taking this action" on Wednesday - when a second walkout is scheduled - and said their loss would be felt.
In a firm stalemate, medical professionals walked out of routine and emergency care at 8am to show their disagreement of Health Secretary Jeremy Hunt's proposed contract changes whereby an overall pay rise was offered in place of pay for "unsociable" hours.
Other doctors and staff members have been put in place to care for those who are vulnerable and in emergency situations, but patients have been warned to think twice before using services over the two days.