The U.N. envoy to the Mideast says it's the "last chance" to prevent an all-out conflict between Israel and Gaza militants.

Nikolay Mladenov said on Monday that the "risk of war remains imminent," a week after a cease-fire between Israel and Gaza's Hamas rulers ended the worst fighting since a 2014 war.

The spate of violence killed 25 Palestinians, including 10 militants, and four Israeli civilians.

Mladenov, inaugurating a solar power plant for a Gaza hospital, said parties must "consolidate the understandings" of the cease-fire.

The deal, mediated by Egypt, Qatar and the U.N., promises to let in fuel and humanitarian aid and ease the movement of people from the blockaded territory.

A Qatari cash infusion, meant for thousands of needy families as part of the cease-fire understandings, arrived Monday.