Hours ahead of the United Progressive Alliance-Left Coordination Committee meeting on Wednesday night, Prime Minister Manmohan Singh said the Nandigram violence was a sad incident and should not have taken place.

"It was a very sad incident. It should not have happened," Dr Singh said in his first public reaction to the violence that left 14 people dead in Nandigram last week.

The prime minister was speaking to reporters on the sidelines of the Defence Investiture Ceremony at Rashtrapati Bhavan.

The issue had rocked both House of Parliament with the Bharatiya Janata Party-led National Democratic Alliance opposition stalling proceedings, demanding the resignation of Left Front government in West Bengal.