New Delhi, Feb 1 (IANS) The Congress Monday rejected Nationalist Congress Party (NCP) leader P.A. Sangma's contention that the prime minister should belong to the Lok Sabha.

Party spokesman Abhishek Manu Singhvi called it an 'old issue' that did not deserve an answer. 'They do not deserve to be dignified by any answer,' he said.

Sangma had said Saturday in Goa that in a parliamentary system, a country must elect its prime minister from the lower house.

Prime Minister Manmohan Singh is a member of Rajya Sabha, the upper House of parliament.