Describing West Bengal Chief Minister Buddhadeb Bhattacharjee as a "personal friend", Prime Minister Manmohan Singh has yet again said that the Congress-led UPA is open to an alliance with the Left for government formation after the Lok Sabha polls.

"There can be an understanding with the Communist Party of India-Marxist (CPI-M) for installing a government. There are no permanent friends or foes in politics," Manmohan Singh.