Bengal Congress chief Somen Mitra met Sonia Gandhi on Friday and secured the green-light for the party to contest bypolls in three Assembly seats jointly with the Left Front, said sources in the Congress.

Mitra, who visited the Congress’s interim president in New Delhi in the evening, sought her clearance for the electoral understanding in Kaliaganj, Kharagpur Sadar and Karimpur Assembly constituencies.

“Somenda told Soniaji that an agreement was reached between the state leadership of the Congress and the CPM to go for a 2:1 seat-sharing. While the Congress will field candidates in Kaliaganj and Kharagpur Sadar — seats of our strength, the CPM will have its nominee in Karimpur,” said a Congress insider.

“Soniaji readily agreed, saying if the Left is indeed willing, there is no need for delay in finalising the deal,” added the leader.

Two Assembly seats fell vacant after the incumbent MLAs had been elected to the Lok Sabha. While Karimpur’s Trinamul MLA Mahua Moitra is now the Krishnagar MP, Dilip Ghosh who represented Kharagpur Sadar in the Assembly became the Midnapore BJP MP.

The Kaliaganj seat fell vacant after Congress MLA Pramatha Nath Roy passed away in May.

Mitra, who met Sonia along with state Congress leaders Abdus Sattar and Subhankar Sarkar, will discuss her instructions at a meeting with party functionaries on Monday.

The Congress and the Left Front had come close to forging an alliance for the

Lok Sabha elections this year, but it didn’t materialise finally.