The Labour Party may be banned from holding its conference in Brighton if it fails to tackle anti-semitism.

The threat was made by the Labour leader of Brighton and Hove City Council, Warren Morgan.

Councillor Morgan said in a post on Facebook: “Anti-semitism will not be tolerated in the city. I have told the Labour Party general secretary this today.”

He shared publicly a letter that he sent to general secretary Iain McNicol.

In the letter he singled out a local campaigner Tony Greenstein, who comes from an Orthodox Jewish family but campaigns for a boycott of Israel over Palestinian issues.

The letter followed a Labour conference fringe event at the Friends’ Meeting House in Brighton at which anti-semitic views were reported to have been expressed.

According to the Guardian newspaper: “Labour’s deputy leader, Tom Watson, has said the party will investigate how it gave a platform at a conference fringe event to a speaker who said people should be allowed to question whether the holocaust happened.

“The remarks by the Israeli-American author Miko Peled have renewed alarm about antisemitism in the Labour party.”

Mr Peled, who is also Jewish, said that did not deny that the holocaust had happened but felt that it was important to debate openly with those who did.

Councillor Morgan’s letter said: “I hope that you and the entire Labour team in Brighton and Hove are enjoying your stay and that the facilities offered by the Brighton Centre are everything that you would expect from us.

“As a city we very much appreciate the business that conference brings to our hotels, restaurants and shops.

“I am, however, very concerned at the anti-semitism being aired publicly in fringe meetings and on the floor of conference.

“We have a significant Jewish community in Brighton and Hove and I met with them only last week to discuss the anti-semitism already on our streets, causing them fear and alarm.

“We have the prominent activist and suspended Labour Party member Tony Greenstein here, who indeed was present at the fringe meeting where it was suggested that Holocaust denial should be allowed. His expulsion, in my opinion, is long overdue.

“As the Labour leader of Brighton and Hove City Council, I will undoubtedly face questions as to why we allow any event where anti-semitic views are freely expressed to happen in the city, particularly on council premises.

“As a Labour Party member I expect the inquiry announced today to take firm action. As leader I will need reassurances that there will be no repeat of the behaviour and actions we have seen this week before any further bookings from the party are taken.

“I must apply the same standards to Labour as I would to any other party conference or political event. While none of us can control what is said at meetings we do not run, I have to make the strongest possible representation on behalf of the residents of the city who are Jewish.

“We are a city of sanctuary and I have to speak up against any form of racism as and when it is given a platform in the city.”

This morning on his blog he wrote a post headed: “Standing up to racism.”

Councillor Morgan wrote: “Yesterday I made a public statement regarding anti-semitism at the Labour conference in Brighton and Hove.

“As a city, we have clear policies on equalities, discrimination and racism. It is my job as leader of the city council to speak out against racism, bigotry and prejudice in all its forms.

“I’ve done so when the far right came here to march. I’ve done so when refugees faced abuse, when the Muslim community faced hostility in the wake of events elsewhere.

“Whatever my views on conflicts elsewhere in the world, my firm belief is that those conflicts should not be played out by groups or individuals against communities in our city.

“We are a city of sanctuary, where people from all backgrounds should live alongside each other, live and work together, without the wars and conflicts in countries they may have connections with coming into daily life here.

“Our right to free speech is bounded by the rights of others not to have their daily life subject to intimidation and fear.

“People are of course free to criticise and protest against the actions of the Israeli government.

“Jewish people here are no more responsible for those actions simply for being Jewish than Syrian people are responsible for Assad or Americans are for Trump.

“Legitimate debate on the Israel/Palestine issue should not be stifled but neither should that issue it be a justification for the demonisation of an entire group of people based on their ethnicity or religion. My statement was not about that conflict.

“Nor was it about the Labour leadership. Jeremy Corbyn and the front bench have been clear on their condemnation of anti-semitism.

“Conference approved a rule change with the support of 96 per cent of delegates to make anti-semitic behaviour even more explicitly against the party rules than it was previously.

“I’m calling for those rules to be enforced so that we can welcome conference back to Brighton and Hove again.

“Anti-semitism is racism. The Labour Party is an anti-racist party. Brighton and Hove is a city where all should feel safe and secure. These are things which should not be in question.”