He had been suspended from the Congress for criticising state leaders and the party high command.

'Virbhadra Singh should be expelled from the union cabinet following the registration of corruption cases against him. The Congress had taken strong action against tainted ministers like Natwar Singh and Shibu Soren, but why is it maintaining silence on Singh is difficult to understand,' Mankotia told IANS on phone.

'I have already requested Prime Minister Manmohan Singh and Congress chief Sonia Gandhi to expel him from the cabinet,' he added.

The police had sent the CD and their voice samples for analysis at the Chandigarh-based Central Forensic Science Laboratory. The laboratory said the voices of Virbhadra Singh and his wife matched with that on the CD.

Meanwhile, Congress state president Kaul Singh Thakur accused the state BJP government of framing Virbhadra Singh and his wife in false cases before the assembly by-elections of Rohru and Jawali.

'It is a political move by the BJP to defame Singh and his wife before the by-election of Rohru (vacated by Singh). Their aim is just to weaken Virbhadra Singh's wife claim for that seat, but it will boomerang on them,' Thakur said.