New Delhi, Dec 12 (IANS): A The row over a bill to provide reservation in promotions resurfaced in the Rajya Sabha Wednesday morning with Bahujan Samaj Party leader Mayawati asking chairman Hamid Ansari to ensure the smooth functioning of the house during zero hour, forcing its adjournment during question hour.

Mayawati, who got up as the question hour was in progress, told the chairman that running the house smoothly was his responsibility and said that he would not be in the house at noon.

"You go at 12...house should run. To ensure this is your responsibility. When it will be 12, you will not be seen," she said.

Ansari, who seemed surprised at Mayawati's words, told her to allow the question hour to proceed.

"What are you doing. This is question hour," he said.

However, Mayawati persisted with her demand that it should be decided first how the house will run at 12.

"There is disruption at 12. The house is functioning now. First it should be decided (how it will be run)," Mayawati said.

She and BSP members then advanced to the chairman's podium to press her demand.

The then chairman adjouned the house till noon.

Members of Congress and BJP seemed taken aback by choice of words used by Mayawati but did not react.

The house has seen disruptions over a constitution amendment bill to provide reservations in promotions for scheduled castes and scheduled tribes, a major demand of the BJP.

The Samajwadi Party is firmly opposed to the bill and has vowed to block it. Its members have been raising slogans against the bill in the Rajya Sabha.

Under the rules, members are not allowed to cast aspertions on the chair.

The chiarman presides over the question hour while zero hour and subsequent proceedings are generally conducted by the deputy chairman. The chairman, however, returns for important occassions - for instance a speech by the prime minister or when the house is adjourned sine die at the conclusion of a session.