Pro-Palestinian activists have vowed to continue their demonstrations, despite the brokered peace deal between Israel and Hamas tentatively holding.
University societies slammed the agreement as a "so-called peace deal" while others described the plan as "not enough."
The Palestine Solidarity Campaign (PSC) has reiterated its demands for Britons to boycott Barclays on Saturday and has planned a march on November 2.
National convener of the Stop the War coalition, told crowds at a rally: "A ceasefire is important, but it is not enough."
Director of the PSC Ben Jamal said he shared "the relief of the Palestinian people" about the ceasefire but added it was at risk of collapsing.
He said: "Trump’s plan is not a pathway to an enduring peace because it does not address the root causes of the conflict.
"It leaves intact Israel’s illegal military occupation of Palestinian territory and system of apartheid that extends across all of historic Palestine.
"Our campaigns will not end until the Palestinian people have their core rights to self-determination and to return realised, which requires an end to occupation and to apartheid."
Protesters have vowed to continue the marches
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Mr Jamal added the PSC's membership had skyrocketed from 69,000 two years ago to more than 300,000 now.
He told The Times the group had "longstanding campaigns in place before October 2023".
A joint statement by university societies, including UCL, Swansea and Durham said "ceasefire" was "an oppressor’s term."
The caption to the Instagram post concluded: "Our movement is nowhere near finished, and we will continue to demand our universities, corporations and governments to divest, sanction and boycott the Zionist state of Israel."
Demonstrators from the "Palestine Coalition" gathered in London over the weekend | REUTERSLATEST DEVELOPMENTS
Your Party co-leader Jeremy Corbyn issued a statement saying: "We must continue to campaign for the only path to a just and lasting peace: an end to the occupation of Palestine.
"One day, everyone will have always been against this. We will not rest until Palestine is free."
A Green Party spokesman said: "We need to continue to highlight the genocide that has taken place in Gaza and to bring to account all those who have committed war crimes."
Liberal Democrat leader Sir Ed Davey said: "This must be the first step towards a two-state solution and a lasting peace."
Islington North MP Jeremy Corbyn has regularly addressed the crowds at Palestine marches
| PAIn Gaza, aid workers are preparing for the opening of the Rafah crossing with Egypt to let Palestinians in and out, but set no date as Israel traded blame with Hamas over violations of the ceasefire deal.
A dispute over the return of hostages' bodies held by terror group Hamas threatens to derail the truce and other unresolved elements of the plan, including disarmament of militants and Gaza’s future governance.
Israeli government spokesperson Shosh Bedrosian told reporters Israel remained committed to the agreement and continued to uphold its obligations, demanding Hamas return the bodies of the 19 deceased hostages it had not handed over.
Hamas has handed over 10 bodies but Israel said one was not that of a hostage, with a spokesman saying it remained committed to the Gaza agreement and to handing over all the remaining bodies of hostages.
However, they admitted returning the remains may take time as some were buried in tunnels destroyed by Israel and others were under the ruins of buildings that Israel had bombed.