Home Secretary John Reid has attacked the decision to close Monkland Hospital's accident and emergency unit.
Dr Reid said NHS Lanarkshire had ignored his constituents' views
Dr Reid, who represents Airdrie and Shotts, said he was "extremely disappointed" at NHS Lanarkshire's plans to shut the department.
He said the health board had failed to consider the views of 29,000 of his constituents.
NHS Lanarkshire's medical director Dr John Browning said the closure would allow for better quality care.
The unit is one of three emergency facilities in the area which health officials said could not be sustained in the long term.
The decision spared Hairmyres casualty department in East Kilbride, while a department at Wishaw General was exempt from the evaluation process.
Dr Reid, a former UK Health Secretary, joined campaigners in a mass protest outside the hospital in April.
In a hard-hitting statement about the health board's recommendation, he said: "I am extremely disappointed with the decision that NHS Lanarkshire has made to close the Monklands hospital accident and emergency department.
"The board have failed to consider the opinions of the 29,000 constituents of mine who signed a petition organised by Karen Whitefield MSP objecting to this closure.
"Also NHS Lanarkshire have conspicuously failed to explain how this decision will improve the health of the people of Airdrie and Shotts."
He added: "At the beginning of the consultation process I, and other colleagues, were assured by NHS Lanarkshire that they would listen to the opinions of the people of Lanarkshire.
"At no point in their decision has NHS Lanarkshire demonstrated, as a result of the overwhelming representations made in support of Monklands A&E, that they had done so much as consider altering their preferred option of closing this vital unit."
Monklands will be downgraded to a planned care hospital
Dr Reid said the closure would also increase health inequalities in the area.
Fellow campaigners claimed Monklands was the most efficient A&E in the area and served the most deprived population of Lanarkshire.
Health board officials said the decision had been made on the issues of cost, emergency services access, and how best to develop primary care for people in the area.
Dr Browning said: "A huge amount of effort has gone into identifying the issues.
"All the hospitals in Lanarkshire are currently busy but we are not looking at what happens now.
"We had to make some very difficult choices about what was best for the future.
"The important thing is that by making this decision we can achieve the best quality of care for the people of Lanarkshire."
If ratified by the Scottish Executive's health department, Monklands' A&E unit will be replaced by a nursing-led minor injuries clinic from as early as 2009.