“I expect the police to use the full force of the law against displays of support for Hamas, other proscribed terrorist groups or attempts to intimidate British Jews,” Braverman wrote on X, formerly Twitter.
Police in Canada’s capital announced an increased presence at sensitive religious areas.
“Today’s attack on Israel has an impact on our own community in Ottawa,” a statement said.
“We have increased police presence in areas of religious significance including synagogues and mosques.
“We are also reaching out to community partners to ensure they know we are here to support them. Hate Crimes will not be tolerated and will be fully investigated.”
The French government focused on synagogues and Jewish schools in cities across the country.
Interior Minister Gerald Darmanin sent an urgent message to regional officials to reinforce surveillance.
“At a time when terrorist attacks from Gaza are hitting Israel, I ask you to immediately step up vigilance, security and protection of Jewish community sites in France,” he wrote in the message seen by Agence France-Presse.
He called for a “visible and systematic static presence”, and the use of soldiers from France’s Operation Sentinelle, a force deployed across the country since the 2015 terror attacks.
France’s Jewish population, estimated at more than 500,000, is the largest in Europe and the third-biggest in the world, after Israel and the United States.
In Germany, Berlin boosted police protection of Jewish and Israeli institutions, while some Palestinian supporters took to the streets of the capital to celebrate the attack.
“In Berlin, police protection has been immediately stepped up,” interior minister Nancy Faeser told Bild newspaper.
“The federal government and the regions are closely coordinating their actions.”
Authorities were also closely watching “potential supporters of Hamas in the Islamist sphere,” she added.
Berlin police posted photos on social media showing “people celebrating the attacks on Israel by passing out pastries”.
Hundreds of people gathered on Saturday in major cities including on Tehran’s Palestine Square, carrying Palestinian flags.
Billboards celebrating the offensive Hamas has dubbed “Al-Aqsa Flood” were put up the capital, including one declaring: “The great liberation operation has begun.”
Crowds in some cities set off fireworks and torched Israeli flags.
Others marched in Palestinian colours while motorists honked their horns in jubilation.
The Iran-backed Shiite movement Hezbollah staged a rally on Sunday in Beirut amid chants of “Death to Israel.”
Hezbollah said it had fired on Israeli positions in the contested Shebaa Farms border area, “in solidarity” with Hamas.
Senior Hezbollah official Hashem Safieddine said the strikes were a message to Israel that “it’s our right and duty to target the enemy so long as it occupies our land”.
Thousands of Turks joined a march in Istanbul to back the Palestinians.
“The Palestinian people are only defending their homeland, it has nothing to do with terrorism,” said 54-year-old Sahin Ocal, a member of one of the associations that organised the protest.
Israeli as well as US flags were burned during a protest in the capital Sanaa which is controlled by Houthi militiamen backed by Iran.
Militiamen were on the streets shouting: “Death to America, Death to Israel.”
A pro-Palestinian demonstrations was expected to take place in the holy Shiite city of Kerbala later on Sunday.
About 100 people had gathered in the heart of the capital Baghdad on Saturday to celebrate the Hamas assault. They stamped on and set fire to Israeli flags chanting: “No to America, No to Israel.”