Former Prime Minister Manmohan Singh, whose tenure as Rajya Sabha member ended in June this year is set to return to the Upper House from Rajasthan, party sources said.
A Congress source said Manmohan Singh will be the party's candidate for the Rajya Sabha.
He said the former Prime Minister will file his nomination on August 13.
Manmohan Singh has represented Assam in Rajya Sabha for 28 years.
The Rajya Sabha elections in Rajasthan was necessitated after the death of BJP MP Madan Lal Saini, who passed away in a Delhi hospital.
Saini was elected to the Upper House last year when the BJP was in power in the state. The Congress has a majority in the 200-member Assembly.