Dec. 17 (UPI) -- Demonstrators on the streets of Britain's two largest cities, chanting or displaying "globalize the intifada" signs or protesting in other ways that intimidate the local Jewish community, face arrest, the country's two most senior police chiefs warned Wednesday.

In a joint statement, London Met Commissioner Sir Mark Rowley and Greater Manchester Police Chief Constable Sir Stephen Watson said Sunday's terror attack targeting Jews celebrating Hanukkah on Bondi Beach in Australia had compelled them to take a tougher line.

They said the backdrop was of rising domestic and international anti-Semitic attacks, protests and hate speech that have left British Jews in a state of fear that was disrupting their daily lives, forcing them to use private and police security and fence in their children's schools.

"The words and chants used, especially in protests, matter and have real-world consequences. We have consistently been advised by the Crown Prosecution Service that many of the phrases causing fear in Jewish communities don't meet prosecution thresholds. Now, in the escalating threat context, we will recalibrate to be more assertive."

Rowley and Watson said that despite problems with the laws they had to work with, use of "globalize the intifada" in chants and on placards would no longer be tolerated.