The Israeli government ban on UNRWA over national security concerns and links to terrorism began Jan. 30. UNRWA has called the move by Jerusalem as "disastrous."

The U.N. Palestinian relief agency UNRWA said on Friday that if its humanitarian work in Gaza is forced to halt, it would put a ceasefire deal between Israel and Hamas at risk.

The directive came in a letter to the U.N., after the Israeli Parliament banned the relief agency that has aided Palestinian refugees for decades.

In the Shuafat refugee camp, a hardscrabble district in east Jerusalem surrounded by a hulking concrete wall, intense security checks make venturing out exasperating.

Israel demands UNRWA halt operations in Jerusalem by January 30, citing Hamas ties and security risks. The move follows Knesset legislation severing ties with the agency.

The ban effectively cuts off the UN aid agency from delivering critical aid to Gaza, putting millions of Palestinians at risk after 15 months of war have devastated the region.

Britain, France and Germany on Friday reiterated their "grave concern" over Israel implementing a law forbidding any contact between its officials and UN Palestinian relief agency UNRWA. "We urge the government of Israel to work with international partners,

The U.N. relief agency UNRWA warns that halting its operations in Gaza could jeopardize the fragile ceasefire between Israel and Hamas. This ceasefire, which paused a prolonged conflict, facilitates humanitarian aid and prisoner exchanges.

Legislation that goes into effect on Thursday bars UNRWA from operating in the country. That will affect aid delivery to Gaza and beyond.

Israel had delayed their release in protest against the way the seven hostages freed by Hamas were treated as they were handed over to Red Cross staff in Khan Younis.

Israel on Thursday formally banned the main United Nations aid agency for Palestinian refugees from operating on its territory, despite heavy diplomatic backlash. Humanitarian officials warn the move could have a disastrous impact on aid delivery and jeopardise regional stability in the long term.