Indian Prime Minister Narendra Modi yesterday tried to reach out to the Muslim community in the country, declaring that "unity in diversity is India's uniqueness".

He reiterated that his government did not discriminate along religious lines as widespread protests continued throughout the country against legislation on a citizenship Act that critics have denounced as divisive and anti-Muslim.

At least 20 people have been killed in the unrest triggered by the Citizenship Amendment Act (CAA), which provides for Indian citizenship for non-Muslim illegal immigrants from Bangladesh, Pakistan and Afghanistan.

Mr Modi was speaking at a rally kick-starting his Bharatiya Janata Party's (BJP) election campaign in the capital city New Delhi, where elections are likely by February.

The BJP is keen to wrest power in the capital from the Aam Aadmi Party.

Mr Modi, the leader of the BJP, which has its roots in Hindu nationalism, dismissed criticism that his government was anti-Muslim.

He said: "The CAA is not aimed at any Indian citizen, whether they are Hindu or Muslim."

He added: "Look at my work... is there any discrimination. I provided (cooking) gas connection (to the poor)... did we ask for anyone's religion?"

Mr Modi is facing the biggest challenge in his second term in power following the passage of the CAA two weeks ago.

The legislation sparked protests initially in the north-east, where there is fierce opposition to the naturalisation of all immigrants, who are regarded as a threat to the local culture.

It was a police crackdown on protesting students of Jamia Millia University in New Delhi on Dec 15 that led to an explosion of anger, particularly in universities and colleges, across the country.

Students have since been at the forefront of the protests.

Statements by multiple BJP leaders, including Home Minister Amit Shah, over the implementation of a National Register of Citizens (NRC) next have added fuel to the fire, particularly among Muslims.

The NRC has been carried out in the north-eastern state of Assam, and up to 1.9 million people, including Hindus and Muslims, have found themselves excluded from the register, with critics slamming the exercise as arbitrary. They said people had been left out for minor infractions such as misspelt names in documents, a common problem in India.

Hindus will now get protection under the CAA, but not Muslims.

Mr Modi addressed some of the concerns about the NRC at the rally, saying that the government has so far not taken any steps to bring it into effect countrywide.

"Muslims will not be sent to detention centres, nor are there any detention centres in India. These are lies," said Mr Modi. He was referring to rumours of detention centres being set up in different parts of the country after work on one in Assam.

Even as the Prime Minister was addressing his supporters, protests were reported in several parts of the country as opponents pressed for the government to withdraw the CAA, something the Home Minister has said was not possible.

But the BJP has found itself in the unenviable position where many of its own allies, worried about blowback, have said they would not implement the CAA, even though it is a law, or the NRC.

Among them is Janata Dal U, whose leader Nitish Kumar is a key BJP ally heading the government in Bihar state.

Analysts said it was crucial for Mr Modi to clarify the government's position.

"When the protests started, many thought that the Prime Minister would step in and assuage sentiments. It is good he has done it now, though I just wish, for the sake of unity and peace, it had been done earlier," said Dr Sandeep Shastri, the pro-vice-chancellor of Jain University. "There have been so many rumours spread about this. Now, he has to do damage control."

The BJP is also rolling out a massive communication campaign on the CAA, with plans to hold 1,000 rallies and 250 media conferences over 10 days.

Some believe Mr Modi, a master communicator, is, for the first time, facing a communication crisis.

"They are saying they are being misunderstood and the Act is misunderstood. But they are not able to properly communicate their position," said Dr N. Bhaskara Rao of the Centre for Media Studies.