BSP chief Mayawati on Sunday attacked the Congress and the Samajwadi Party, saying they should not speak on reservations as they colluded in opposing legislation giving quota in promotions to Scheduled Castes (SC) and Scheduled Tribes (ST) when the Congress-led UPA was in power.

Addressing a press conference, she also backed the Centre's bills on 'one nation- one election', stressing it will reduce expenses and ensure public welfare works continue uninterrupted. She urged other parties to also support the measure.

Mayawati demanded that reservations for SC, ST and OBC be included in the Ninth Schedule of the Constitution to prevent any tampering. Central and state laws listed in the Ninth Schedule are exempt from judicial review.

 During the discussion on the Constitution in Lok Sabha, the ruling side and the opposition, especially the Congress and the Samajwadi Party, to woo Dalit and OBC voters, have said a lot of "baseless" things about reservation issue in which there is "not even an iota of truth", she told reporters.

"And it would have been better if these two parties (Congress, SP) had remained silent on this issue in Parliament, because during the time of the Congress party's government at the Centre and with the connivance of this party, SP had strongly opposed the Constitutional Amendment Bill related to reservations in promotion of SC and ST communities.

"This bill was torn and thrown away by SP in the Parliament itself and ... Is still pending in the Parliament," she lamented.