The Minister for Health, Mr Martin has urged the Medical Defence Union to reverse its decision not to cover obstetricians in certain cases.
The MDU made a decision to withdraw cover from certain obstetricians in a row over the soaring cost of lawsuits.
Mr Martin this morning accused the union of abandoning its responsibilities to Irish obstetricians.
"I am accountable to Dáil Éireann for the spending of taxpayers money and I cannot expose the Irish taxpayer to claims of up to €400 million.
"Particularly when the MDU took subscriptions from Irish doctors (which the Government then refunded to the doctors) for the last 25 years.
"The Government has been making every effort to resolve this issue," Mr Martin said.
The MDU rejected the criticism, insisting it has "always been open" about the extent of its members' obstetric liabilities.
Dr Michael Saunders, MDU chief executive, said the union had met officials from the Department of Health 15 times since February in an effort to reach agreement. "We are even further away from a solution to this problem, yet we have done everything in our power to bring this matter to a satisfactory conclusion."
Dr Saunders claims to have been locked in a row with the Government over who should be responsible for past liabilities for the last ten years. He claims the Department of Health has blocked the MDU from charging the appropriate subscriptions to cover costs.
When the level of damages awards against obstetricians dramatically escalated in the 1990s, the MDU increased its subscription rates to cover costs.
As a result 35 obstetricians transferred from the MDU to the Medical Protection Society and the Department of Health agreed to cover court awards exceeding subscription costs.
The MDU was then forced to provide cover for liabilities arising out of clinical events which occurred before the agreement, in 2001, and without the funding from so many obstetricians subscriptions.
The dispute is expected to end up in the courts.