"You remain neutral. I will tell you later what stand to be adopted on the FDI issue," Mayawati, a member of Rajya Sabha, is learnt to have told BSP MPs here.
In signals that she was not inclined to support the opposition in attacking UPA government on the issue, she is also believed to have asked the MPs not to rush to the well of the House.
Her party has 21 MPs in the Lok Sabha and 15 in the Upper House.
Samajwadi Party is meeting tomorrow, after which its chief Mulayam Singh Yadav, who is also the Parliamentary Party leader, is expected to announce its stand.
Yadav has often said his party does not want to pull down the government in order to keep communal forces at bay. At the same time, he has asked his partymen to prepare for the Lok Sabha polls as they could be held before 2014.
SP has 22 MPs in the Lok Sabha and nine in Rajya Sabha.
Both the Uttar Pradesh parties have remained supportive of UPA government in Parliament.
Prime Minister Manmohan Singh had recently hosted Yadav and Mayawati a dinner and lunch respectively to garner their support ahead of the session.
The stage is set for a stormy winter session beginning tomorrow with a united opposition firm on discussion on FDI in retail under a rule that entails voting, a demand the government is not ready to accept at least for now.
An all-party meeting convened by Lok Sabha Speaker Meira Kumar on the eve of the winter session saw the Opposition making common cause on the issue of FDI in retail accusing the government of violating the assurance given to Parliament that all stakeholders would be consulted before going ahead with the decision.