The event, organised by the Palestine Solidarity Campaign (PSC), saw a large crowd block traffic near Victoria Embankment on Saturday afternoon.
Holding banners, placards and flags, the demonstrators let off green and red-coloured smoke and chanted, blocking traffic as they marched.
Some demonstrators could be seen wearing costumes, masks and face paint, while others were draped in the Palestinian flag.
A Met Police spokesman said there were seven arrests on the day including a racially aggravated public order offence and a homophobic public order offence.
Three of the arrests were for violent disorder. All those arrested were men and they were all taken into custody.
Chief Superintendent Andy Walker said the main event went ahead “safely and without incident”.
He added: “We reacted quickly to the decision by a small group to break away from the main protest and where offences were identified, arrests were made.
“As we emerge from the Covid-19 pandemic we are still striking a careful balance between the rights of demonstrators and the need to keep Londoners safe and prevent a resurgence of the virus. I am grateful to the majority of those who attended this event, and to our officers, for helping to achieve those objectives today.”
Chants of “We are all Palestinians” could be heard during the march.
As the crowd reached Downing Street, chants of “Boris Johnson, shame on you” rang out.
A temporary stage has been set up in Hyde Park where a number of speeches will be made this afternoon.
In a tweet, the PSC said: “Join us to stand in solidarity with the Palestinian people & call on the Gov to take action against Israel's brutal violations of intl. law.”
At the rally, people waved Palestinian flags, held banners and chanted as they began their march towards Hyde Park.
The protest is taking place amid a ceasefire between Israel and Palestinian militant group Hamas.
The ceasefire began on Friday, bringing to an end 11 days of fighting which saw more than 250 people killed, most of them in Gaza.
Both Israel and Hamas claimed victory in the recent conflict.
At the protest, former Labour shadow chancellor John McDonnell said: "Yes, a ceasefire has been negotiated and we welcome a ceasefire.
"But let's be clear, there will be no ceasefire in our campaign to boycott, disinvest and sanction the Israeli apartheid state.
"The message is clear, we will not cease our campaign in solidarity until there is justice.
"So let's make it clear, no justice, no peace."
It comes as other protests are taking place across the capital, including an anti-racism protest to commemorate George Floyd, who died almost one year ago.
Around a dozen campaigners from Stand Up To Racism held placards and chanted outside the US embassy in Nine Elms on Saturday morning.
Police officers watched on as protesters unveiled banners reading “Black Lives Matter”.
The activists chanted “No justice, no peace, no racist police” before a number of speeches were made on “systemic racism which exists in the UK”.
Elizabeth Adofo, an organiser of the protest, said: “We are here today to mark one year since the murder of George Floyd at the hands of racist police officers.
“And it’s been one year since everyone across the world marched in solidarity with the Black Lives Matter movement.
“We’re here to say it’s still important, even after the cameras stop showing up, even after the big crowds on the streets, it is still important to spread that message.
“It doesn’t matter that Derek Chauvin got convicted, that is a small amount of justice of what he really deserves.”
Protests are taking place in Manchester, London, Glasgow and Swansea.
They will be followed by an online rally which will include speeches from university professors, solicitors, race equality campaign groups and former shadow home secretary Diane Abbott MP.
Meanwhile, animal rights protesters have disrupted McDonald’s distribution centres across the country a bid to pressure the fast-food chain to become fully plant-based by 2025.
Animal Rebellion, who claim the action will impact roughly 1,300 restaurants, are using trucks and bamboo structures at distribution sites in Hemel Hempstead, Basingstoke, Coventry and Heywood, Greater Manchester, to stop lorries from leaving depots.
The organisation said they intend to remain at the sites for at least 24 hours, causing “significant disruption” to the McDonald’s supply chain.
A McDonald’s spokesman said: “Our distribution centres are currently facing disruption.
“We are assessing the impact on deliveries to our restaurants and to menu items.
“We apologise to our customers for any disappointment caused.”