New Delhi, (PTI) Bihar Chief Minister and JD(U) chief Nitish Kumar today met Congress President Sonia Gandhi here and is learnt to have advocated unity among opposition parties to take on the BJP-led NDA.

JD(U) also used the meeting to call for a joint opposition candidate for the election to the President's post and urged Gandhi to take the lead in the matter.

Its spokesperson K C Tyagi, however, insisted that the issue of presidential election was not discussed in the meeting and added it was his party's view that a strong joint opposition candidate will be in national interest.

"There should a joint opposition candidate for the top Constitutional post and Sonia Gandhi being the leader of the largest opposition party should take the lead," he said.

Kumar has already taken up the matter with leaders of the Left parties and received a good response, he said.

Another senior JD(U) leader said Kumar's visit to Gandhi's residence was a courtesy call as the Congress is the party's ally in Bihar and also because Gandhi had been ill for some time.

"He did speak about the need for unity among opposition parties," he added.

Kumar has been calling for forging an alliance of secular parties at the national level on the lines of the 2015 electoral grand alliance or 'Mahagathbandhan' in Bihar to take on the BJP-led NDA under Prime Minister Narendra Modi.

The Congress is a partner in the Bihar government with Kumar's JD-U and Lalu Prasad's RJD, after the three parties contested and won the assembly elections as part of the grand alliance.