Tory MPs, charity bosses and business leaders are poised to boycott a Downing Street Eid event as a result of the Government's support for Israel.
The event is held annually at Downing Street. It will be hosted by Rishi Sunak later today.
But some invitees are said to be planning to skip the event in protest.
Sources in Downing Street told the BBC they are concerned over the number of people who might decline to attend the reception.
Tory MPs, charity bosses and business leaders have threatened to boycott a Downing Street Eid event as a result of the Government's support for Israel
PA
Baroness Warsi is said to be one of the Conservative politicians planning to avoid the event, alongside two Tory MPs.
Warsi resigned as a minister in the Foreign Office in 2014, while David Cameron was prime minister. She quit saying the Government's policy over Gaza was "morally indefensible".
Asif Ansari, a leading businessman and charity fundraiser, told the BBC: "As a Muslim, I think it's very important for the Muslim community to have good relations with the British government.
"However, I feel very, very strongly this year with the position that the British government is taking.
"They are supporting Israel who stand accused of genocide, they stand accused of war crimes, the deprivation of water and food to women and children has left many starving and lastly, the killing of three British aid workers - after which Lord Cameron has said the UK would continue to supply arms to Israel - was an absolute red line."
One person from a charity who has decided to attend the Eid event said they have chosen to do so because they "believe it is important to engage with the government at this time of conflict".
Lord David Cameron today urged invitees to attend the reception, calling for people to "put aside political differences" amid reports some are planning to boycott the event.
A No10 spokesperson said: "The prime minister looks forward to welcoming members of the Muslim community to the Eid reception in Downing Street later this week and celebrating their contribution to public life.
"But we share the deep concern that many British Muslims have over the humanitarian crisis in Gaza and our priority has always been to prevent further escalation in the region.
"That's why we have long called for an immediate humanitarian pause with progress towards a sustainable ceasefire, and consistently urged Israel and all parties to the conflict to abide by International Humanitarian Law."
There have been growing calls for the UK to stop arms sales to Israel, with 600 lawyers writing to the government saying weapon exports must end because the UK risks breaking international law over a "plausible risk of genocide" in Gaza.
Israel rejects the claim of genocide as "wholly unfounded".
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