Prime Minister Manmohan Singh on Wednesday apologised to the Lok Sabha on behalf of the government for certain undesirable remarks by a Congress member against former Prime Minister Atal Bihari Vajpayee.

"Yesterday I was not present in the House. I have heard some undesirable remarks were made by a member of the ruling coalition which was inappropriate. "On behalf of our government, I apologise to the House," Singh, who returned Tuesday night after a three-day visit to Russia, said.