The Conservative Party's investigation into Boris Johnson's controversial comments over the burka cannot be a "whitewash" the Muslim Council of Britain (MCB) has said.
Following the former foreign secretary's comments that Muslim women who wear the burka look like "letter-boxes" or "bank robbers", the MCB's letter to Theresa May is expected to state that "no-one should be allowed to victimise minorities with impunity".
Miqdaad Versi, the Assistant Secretary General of the MCB, told ITV News that there must be "transparency" around the investigation into the comments, which were a "a deliberate action to stoke tensions".
He continued the remarks were "a problem for someone who is a senior politician who is respected around the country, yet he ends up saying this vile language.
"It's a problem for us, and hopefully it's a problem for the whole of society."
Speaking on BBC Radio 4's Today programme earlier on Monday, Mr Varsi added that the Tories "can't ignore the consequences" of Mr Johnson's words, citing reports by the Tell Mama project - which monitors anti-Muslim violence - that there has been an increase in incidents of abuse aimed at women wearing the niqab or hijab over the past week.
Mr Versi continued that this meant that if the investigation was not carried out properly then it would signify that the Conservative Party believes "that when Muslim women are attacked on the street that is an entirely trivial matter".
Boris Johnson greets the media with cups of tea
When questioned that it is not for the investigation into the comments "to draw links", Mr Versi reiterated that the party needs to understand that "there are actions" and "consequences" from what Mr Johnson had said, and there needs to be "accountability".
He continued that the Conservatives must follow their code of conduct when carrying out the investigation.
Currently the complaints against Mr Johnson's comments are being looked at by an investigating officer, who can dismiss them if they are found to be obviously trivial, lacking in merit or unable to be fairly investigated.
If the investigating officer deemed that an investigation should be carried out, a disciplinary panel would then be put in place.
Mr Versi added that the "Muslim women who have suffered" - received verbal or physical abuse due to their decision to wear the burka or niqab - must be listened to.
He added that Mr Johnson had " deliberately used words to stoke up hatred", words which are "used by the far-right and that are heard across the country".
Mr Johnson has yet to respond to allegations of Islamophobia following the comments made in his Daily Telegraph column last week, nor has the 54-year-old apologised following calls from the Prime Minister and Conservative chair Brandon Lewis.
In the column, Mr Johnson did not call for burkas or niqabs to be banned, and supported the right of Muslim women to wear the veil if they wanted.
In his latest column for the newspaper, Mr Johnson sought to steer away from the row, instead writing about proposals to encourage house building.
After returning from a holiday at the weekend, Mr Johnson did not offer comment to reporters gathered outside his Thame home, and instead offered them tea.