The Opposition parties should introspect over their "irresponsible" statements about the Covid vaccination programme of the Modi government that has proved to be the "biggest and fastest" in the world, BJP president JP Nadda said on Monday.

In a visit to a vaccination centre at All India Institute of Medical Sciences (AIIMS) here, he congratulated and thanked a team of Union Health Minister Mansukh Mandaviya, state health ministers, medical fraternity and people for making the vaccination campaign a "success".

Over 2.5 crore people were vaccinated on Prime Minister Narendra Modi's 71st birthday on September 17, setting a world record in vaccination. It proves that this campaign is the "biggest and fastest" in the world, Nadda said.

"The Opposition parties should introspect over their silence on 2.5 crore vaccinations on September 17 and their irresponsible and laughable statements in the past one year on the vaccination drive. They should think what impression they have left on the society and their role in a democracy," he said.

It was his second visit to the AIIMS vaccination centre since the drive began earlier this year. He interacted with people who had come for vaccination at the centre and the medical staff and thanked them for making the drive a success.

The visit by the BJP president was part of the party's 20-day mega campaign, titled 'Sewa Aur Samarpan Abhiyan', launched on Modi's birthday.