London Mayor Sadiq Khan has come under fire for refusing to confirm that he would petition U.K. Home Secretary Amber Rudd to designate all of Hezbollah as a terrorist organization.

The question regarding the terror group’s status was raised last week by London Assembly Member David Kurten (UKIP) in response to the presence of Hezbollah flags during an anti-Israel Al-Quds Day march in London.

“That will close the loophole to stop people marching through the streets of London with a flag with a gun on it,” Kurten said in support of the terror designation during a London Assembly meeting.

At the same meeting, Assembly Member Andrew Boff (Conservative) accused Khan, who is Muslim, of not doing his job, saying the mayor seems to be “avoiding saying, ‘Yes I’ll [confirm the designation with the home secretary].’”

Rudd said she would explore the possibility of banning the annual Al-Quds Day march and designating all of Hezbollah as a terrorist organization.

In the past, the European Union has come under scrutiny for making a distinction between the so-called “military” and “political” wings of Hezbollah, only giving the “military” wing a terror designation.

The grassroots group North West Friends of Israel amassed 20,000 signatures on a petition advocating for the Hezbollah terror designation. Last year, Hezbollah flags were similarly featured at London’s Al-Quds Day, accompanied by placards bearing the words “We Are All Hezbollah.”