Thousands of protesters in major European cities marched in support of Palestine on Saturday.
In London several thousand protesters carrying placards reading "Stop Bombing Gaza" and chanting "Free Palestine" marched towards the Israeli embassy in Kensington High Street.
Organisers claimed as many as 100,000 people had gathered for the demonstration, but London police said they were unable to confirm any figure.
"The group is spread across a large area, which makes it impossible to count them," a Metropolitan Police spokesman said.
"Officers are engaging with a group of people who have gathered for a demonstration in central London this afternoon," the police said in a separate statement, adding that a plan was in place to curb the spread of Covid-19.
"This time is different. This time we will not be denied anymore. We are united. We have had enough of oppression," Palestinian Ambassador Husam Zomlot told the demonstrators.
"Today we are saying enough, enough with the complicity," he said.
Simon Makepace, a 61-year-old accountant told AFP he joined the protests because "the whole world should be doing something about it, including this country".
He was critical of the US, which he said was unfairly backing Israel, and urged Washington to "make peace and stop what's happening".
Azadeh Pyman, a 50-year-old scientist said she had been raised on the Palestinian cause by her parents and grandparents.
"I'm not Palestinian originally but my heart bleeds for Palestinians," she said. "I think it's the cause that will go from one generation to another generation, until Palestine is free."
In Madrid, about 2,500 people, many of them young people wrapped in Palestinian flags, marched to the Puerta del Sol plaza in the city centre.
"This is not a war, it's genocide," they chanted.
"They are massacring us," said Amira Sheikh-Ali, a 37-year-old of Palestinian origin.
"We're in a situation when the Nakba is continuing in the middle of the 21st century," she said, referring to the "catastrophe", a word used by Palestinians to describe Israel's creation in 1948 when hundreds of thousands fled or were driven out.
"We want to ask Spain and the European authorities not to collaborate with Israel, because with their silence, they are collaborating," said Ikhlass Abousousiane, a 25-year-old nurse of Moroccan origin.
The marches came amid the worst Israeli-Palestinian violence since the 2014 war in Gaza.
Thousands marched in Berlin and other German cities following a call by the Samidoun collective.
Three marches were authorised in Berlin's working-class Neukoelln southern district, home to large numbers of people with Turkish and Arabic roots.
The protesters shouted "Boycott Israel" and threw paving stones and bottles at the police, leading to several arrests.
Other protests were held in Frankfurt, Leipzig and Hamburg with demonstrator @theleovre tweeting these pics.
On Tuesday Israeli flags were burnt in front of two synagogues in Bonn and Muenster.
Police officers used tear gas and water cannon in Paris to try to disperse a pro-Palestinian rally held despite a ban by authorities.
Some threw stones or tried to set up roadblocks with construction barriers but for the most part police pursued groups across the district while preventing any march toward the Place de la Bastille as planned.
Around 500 people rallied in in front of the Israeli embassy in Athens too. Greek police used water cannon to disperse them and minor scuffles ensued.