Lord Pearson of Rannoch is facing a formal complaint from Labour MP Khalid Mahmood, after calling on Muslims to "address the violence in the Qur'an."

Speaking in the House of Lords, Pearson, the former UKIP leader, said: "My lords, are the government aware that Fusilier Rigby's murderers quoted 22 verses of the Qur'an to justify their atrocity? Therefore, is the prime minister accurate or helpful when he describes it as a betrayal of Islam? Since the vast majority of Muslims are our peace-loving friends, should we not encourage them to address the violence in the Qur'an – and indeed in the life and the example of Muhammad?"

The Leader of the House of Lords dismissed his concerns, and now Labour MP Khalid Mahmood has stated his intention to make a formal complaint to the Lord Speaker over Pearson's question.

Mahmood told the Guardian: "I find it absolutely offensive that this guy is still able to say this. I will actually tomorrow make a complaint formally to the lords speaker on this issue. This is not tolerable and it should not be tolerated at all."

Yasmin Qureshi, the Labour MP for Bolton South East, said: "These are lies. Trying to say this comes from some text in the Qur'an or there is some justification in the religion – it isn't there."

Ms Qureshi said that Muslims should not have to "take responsibility" for the actions of extremists, though Lord Pearson had only actually called on Muslims to "address the violence in the Qur'an."

Lord Pearson did not say that Muslims were responsible for the actions of extremists, and was clear to state that the "vast majority" of British Muslims were "our peace-loving friends".

National Secular Society executive director Keith Porteous Wood, said: "Nothing in our society should be beyond discussion or debate. But Lord Pearson is now facing a formal complaint for expressing a view in Parliament. This is a type of farce we should have left behind long ago."

"If Khalid Mahmood – or anyone else – disagrees with Pearson so strongly, then they should challenge him to a public debate or write an article rebutting his arguments. We don't have freedom of speech so that we can only discuss things we're all comfortable with."

Lord Pearson has previously warned of the threat posed by Islamism; in 2013 he said: "What baffles me completely is that when we do speak against these things, when we dare to say that they come from within Islam, we are told that we are the guilty ones, that it us who are stirring up hate."