On Monday at 5 pm, the Rajya Sabha will vote on whether to reserve promotions in government jobs for Dalits and tribals.After a walk-out by the Samajwadi Party, the proposal was debated in the Rajya Sabha on Thursday, with its greatest proponent, Mayawati, arguing for its exigent implementation.Parliamentary Affairs Minister Kamal Nath told NDTV that he will ensure that the "quota bill" is also cleared by the Lok Sabha before this session of Parliament ends on December 20.In Uttar Pradesh, 18 lakh government employees have begun a strike in protest, though essential services, like hospitals, water and power supply, transport services, are exempt.The challenge for the government is that its two life-support systems - the Samajwadi Party led by Mulayam Singh Yadav and Mayawati's Bahujan Samaj Party - have opposing demands.The Samajwadi Party says the move to reserve promotions is unacceptable; Mayawati says it's essential; the main opposition party, the BJP, is reportedly willing to support the legislation with some amendments."Reservation should not be implemented in a manner that it allows reverse discrimination," said BJP leader Arun Jaitley.In the Rajya Sabha, as avowed earlier this week, Mulayam Singh's MPs tried to prevent a debate on the bill by shouting and trying to disrupt proceedings, a strategy that had worked until today in forcing adjournments of the house, effectively paralysing the Rajya Sabha. But the presiding officer, Deputy Chairman PJ Kurien, took firm action against the cacophonous Samajwadi Party MPs. He asked two of them to leave the House and warned that they would be evicted if they did not oblige. Finally, all nine Samajwadi MPs walked out and the debate on the proposed legislation began.

Critics say this was an astute exit strategy - Mr Yadav's putative opposition to the quota bill was recorded, but he did not obstruct the government's efforts to push it through.Neither Mr Yadav nor Mayawati participate in the government at the Centre, but provide external support to the shaky coalition. Last week, they rescued the government, facilitating an important victory in Parliament on the contentious decision to allow foreign supermarkets into India.