Activists gathered in central London for the Stop The Hate national demonstration which included a rally and a march to Whitehall.
In the afternoon and under a large police presence, they held a booming dance party including pink smoke in the central strip of Whitehall in front of Downing Street between the Cenotaph and The Women of World War II memorial.
Other events are being held in Glasgow and Cardiff as part of the Stand Up To Racism campaign.
Banners declaring: âRacism is extremismâ; âfreedom is a constant struggleâ; ârefugees welcomeâ; âsay no to Islamophobiaâ; and âstamp out antisemitism, yes to diversityâ were held by the demonstrators.
Loud cheers broke out as Labour MP John McDonnell, who was shadow chancellor under Jeremy Corbyn, told the crowd outside the Home Office: âI am here today in solidarity with my friend, my colleague, my comrade, Diane Abbott.â
People take part in an anti-racism march in central London organised by Stand Up To Racism and trade unions (Lucy North/PA)
He also led those gathered in a chant of âno justice, no peaceâ, before adding: âIf the Labour party want to be perceived as an anti-racist party, there is one simple step that can be done today, and that is Sir Keir Starmer restoring the whip to Diane Abbott.â
The party suspended Ms Abbott 11 months ago for saying Irish, Jewish and Traveller people do not face racism âall their livesâ.
She withdrew her remarks the same day and apologised âfor any anguish causedâ.
Earlier this week Ms Abbott, who currently sits as an independent MP, spoke out about racism in politics, a day after being denied a chance to take part in a Commons debate about a Tory donorâs criticism of her.
Frank Hester is reported to have said the MP made him want âto hate all black womenâ and that she âshould be shotâ.
Ms Abbott said she had been âupsetâ by the comments, but was âhardened to racist abuseâ.
Protesters hit out at hate and racism in the country (Lucy North/PA)
Prime Minister Rishi Sunak has said that Mr Hester had apologised and his âremorse should be acceptedâ.
Trade unions, the Jewish Socialist Group along with other faith groups and grassroots campaigns were among supporters of Saturdayâs demonstration which the organisers said was part of a âmass campaign by a broad coalition of forces drawing in anti-racists everywhereâ.
They added such action âis going to be critical in the fight to ensure that the politics of racism, division and hate are not allowed to gain a foothold here in Britain and if we are to stop the rise of the new far rightâ.
Mr McDonnell recalled years of campaigning in Britain where activists marched in the streets against discrimination, antisemitism and racism, but he suggested they are now having to protest in response to people who are in power.
Many spoke up in support of Diane Abbott (Lucy North/PA)
He said Ms Abbott is nobodyâs victim, but facing racism âday-in, day-outâ from various sections âtakes it toll, and I want to pay tribute to this woman, her bravery, courage, determination and her solidarityâ, he told the crowd.
Earlier, Mr McDonnell told the PA news agency: âI think that the reason people are mobilising in such large numbers is because we are seeing the rise of racism within our society again.
âPeople of all walks of life, all ages and all denominations are coming together and saying `this is not the society that we want, we have to expose what is happening and at the same time counter itâ.â
He said that Ms Abbott not being allowed to speak in parliament this week, when she was the focus of a race row debate, was âdisrespectful because we have a duty of respect and a duty of careâ.
Mr McDonnell added: âShe should have been allowed to say her piece in respect to what was being said about her and I was absolutely shocked she wasnât given that opportunity. Lessons have to be learned.â
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