New Delhi, July 25 :    New Delhi, July 25:  Even as the Union Cabinet ignored Mamata Banerjee's ultimatum and decided to meet only on Monday, Samata Party MPs demanded that the headquarters of South-Eastern Railway be shifted to Ranchi from Calcutta. Lok Sabha MP Prabhunath Singh and Rajya Sabha MP Rajiv Ranjan Singh, who are close to railway minister Nitish Kumar, said if Mamata was so agitated about the proposed bifurcation of Eastern Railway, she could quit the NDA. 'We cannot trust her. She deserted the NDA on the Tehelka issue and later apologised to George Fernandes and came back. Now what happened to the 72-hour bandh threat? Why can't she straight go to the Prime Minister (and say) that 'I want to take oath'. If she is so sincere about this bifurcation business, she should quit the NDA instead of enacting drama,' they said. Mamata had threatened to call a 72-hour bandh if the decision was not reviewed by July 24, but kept it on hold when the Prime Minister said the Cabinet would discuss the issue. The Samata MPs said they would raise the demand for shifting the head offices of Coal India and DVC to Patna if 'she did not mend her ways'. The big coal mines were in Bihar and Jharkhand and there was no rationale for Coal India to have its headquarters in Calcutta, they said. Reacting to the demand of a group of Jharkhand MPs for a new railway zone, including Dhanbad, at Ranchi, the Samata MPs said the South-Eastern Railway headquarters could be shifted to Ranchi instead. They ruled out any compromise on the Eastern Railway bifurcation, making it clear that Monday's meeting is unlikely to come up with a solution to the tangle. Government sources said Cabinet meetings will henceforth be held on Mondays and Wednesdays instead of Tuesdays and Thursdays/Fridays during Parliament sessions. The move is aimed at easing the pressure on the Prime Minister.