A day after he was declared the UPA's PM candidate in the next polls, Prime Minister Manmohan Singh was on Saturday urged by a key ally to contest for the Lok Sabha, a suggestion brushed aside as "petty details" by the Congress.

Hailing Congress President Sonia Gandhi's announcement of Singh as the PM candidate, Sharad Pawar-led NCP said in the coming elections, he should contest the Lok Sabha polls to give strength to the UPA.

Party spokesman D P Tripathi said that it was for the Congress party to decide from where the Prime Minister should be fielded. Singh is the lone Congress Prime Minister who is a member of the Upper House.

Noting that it was a good thing for the UPA as also the country that the haze around the issue of PM candidate has been cleared, he said "we fully endorse and support her view."

However, Congress spokesman Abhishek Singhvi dubbed the suggestion as "petty details".

"Petty details are unimportant. What is important is that the Congress-led UPA will come back to power and Manmohan Singh will be back as Prime Minister as stated by Congress President with emphatic certainty," he told PTI.

Singh has been a member of the Rajya Sabha since he entered politics in 1991 when the economist-turned-politician became Finance Minister.

His maiden attempt to enter the Lok Sabha in 1999 through the South Delhi constituency was unsuccessful. Singh represents Assam in the Rajya Sabha and is an AICC member from both Assam as also his native Punjab.

Incidentally, NCP had been favouring Singh as the PM candidate of the UPA on the ground that he was a "non-controversial" leader.