US President Joe Biden has suggested that a pause in the fighting between Israel and Hamas in the Gaza Strip appears difficult to achieve by the start of the Muslim holy month of Ramadan.

Talks between Hamas and delegates of Egypt, Qatar and the US were underway toward the goal of achieving a pause in fighting and the release of hostages taken by the Islamic group by Ramadan, which starts around Sunday.

But Hamas announced on Thursday the negotiations had been suspended.

Asked by reporters on Friday about the prospect for a pause in fighting by Ramadan, Biden said, "It's looking tough."

The president previously said it could be very dangerous if the fighting continues during Ramadan.

The humanitarian situation is further deteriorating in Gaza, particularly in the northern parts of the enclave. Reports are coming in that residents have died of malnutrition.

The Canadian government announced on Friday that it will resume funding for the UN agency for Palestinian refugees known as UNRWA, in view of the dire situation in Gaza.

In response to Israel's allegations that some UNRWA staff were involved in the attack on Israel last October, 16 countries, including the US, Japan and Canada, suspended provisions of funds for the agency.

But the Canadian government said it has changed its stance "in recognition of the robust investigative process underway" into the issue.

The US government has announced a plan to build a floating pier on Gaza's shore to transport relief supplies by sea. It says it will be possible to deliver more than two million meals per day if the pier becomes operational.

However, its construction is projected to take up to 60 days.