New Delhi,  Ahead of nomination of Yashwant Sinha, the opposition presidential candidate, the leaders of the Opposition parties will be meeting on Monday in Parliament. NCP supremo Sharad Pawar who is firefighting the Maharashtra crisis has landed in Delhi for the meet. The opposition has been put to test since the NDA announced its candidate.

The big question is who all from the opposition will be present in Monday's meeting as Congress MLAs and MP are busy signing the nomination papers. Sinha will address a press conference on Monday at 4 p.m. and will then begin his campaign.

Sinha on Wednesday had said that the Constitution is being throttled.

"If elected," he said, "I shall not allow the independence and integrity of democratic institutions to be weaponised against political opponents, as is happening now."

"The ongoing attacks on the federal structure of the Constitution, whereby the government is attempting to rob the state governments of their legitimate rights and powers, will be treated as totally unacceptable. I shall also use the authority of my office to check the menacing power of ill-gotten money that is killing the soul of Indian democracy and making a mockery of people's mandate in elections," Sinha told media here.

A dozen-odd opposition parties declared Sinha as their candidate on Tuesday, the same day the BJP declared Draupadi Murmu as its candidate for the post of the President, elections for which are due on July 18.

BSP Supremo Mayawati has already announced support to the NDA nominee while YSRCP and the BJD are on board from day one and the crisis in Maharashtra has put the NDA in a comfortable position in the contest while other political parties may come in support of Murmu. She has already spoken to JMM leader Hemant Soren.

The development comes after JDS leader H.D. Deve Gowda praised the NDA candidate and termed her "suitable" and "non-controversial".