US Secretary of State Antony Blinken said on Monday that the United States and Israel were working towards a plan to vaccinate Gazans for polio after the besieged territory reported its first case of the disease in 25 years.

"We're working with the Israeli government on that, and I believe that we'll be able to move forward with a plan to do that in the coming weeks," Blinken told reporters in Tel Aviv.

"It is urgent. It is vital," Blinken said.

The United Nations has said it already has detailed plans in place to vaccinate children across the Gaza Strip and could start this month.

However, that would require a pause in the fighting and Secretary-General Antonio Guterres has called for two seven-day breaks in the Gaza war to vaccinate the territory's more than 640,000 children.

Blinken, who did not say how the vaccination would take place, said he had a "detailed" discussion on the humanitarian situation in Gaza with Defence Minister Yoav Gallant.

"We very much share the concern about the possibility of its (polio's) reemergence, and we've been working on a detailed plan to make sure that those who need to be vaccinated against it can get vaccinated," Blinken said.

Blinken, who also met for three hours with Prime Minister Benjamin Netanyahu, is pushing to complete a more lasting ceasefire in the 10-month war.

Blinken added that to improve the humanitarian situation in Gaza, "the quickest way to do that, in the most robust way possible, would be through the ceasefire, because that opens up much more space to surge assistance".