Party General Secretary Digvijay Singh told reporters that a CBI probe into the matter was the only option in the two cases in which the chief ministers of neighbouring states are at loggerheads.
Singh, who is in-charge of party affairs in the two states, claimed that the cases have created a situation of constitutional crisis as the charges have been levelled against the chief ministers themselves.
Singh said that the allegation against the Telangana chief minister was equally serious.
He said that the PCCs concerned are filing a public interest litigation seeking a Supreme Court or high court monitored-CBI probe in the two cases.