The Unit­ed States and Iran reached an ini­tial agree­ment Mon­day that would ex­tend their shaky cease­fire and lead to the re­open­ing of the Strait of Hor­muz, but sig­nif­i­cant chal­lenges re­main to end­ing the war, in­clud­ing whether Is­rael will con­tin­ue its of­fen­sive in Lebanon.

De­tails of the deal have not been made pub­lic. The U.S. said it was signed elec­tron­i­cal­ly on Sun­day but that it will not be im­ple­ment­ed un­til a for­mal sign­ing. Pak­istani Prime Min­is­ter She­hbaz Sharif, a key me­di­a­tor, said that will hap­pen Fri­day in Gene­va. Even if the strait — a cru­cial wa­ter­way for the world’s oil and nat­ur­al gas — ful­ly opens then, it will like­ly take months for the glob­al en­er­gy cri­sis sparked by its clo­sure to ease.

Is­rael joined the U.S. in launch­ing the war on Feb. 28, but it is not par­ty to the deal. The Is­raeli de­fense min­is­ter said Mon­day that the coun­try would not with­draw from land seized in Lebanon, where Is­rael is fight­ing the Iran­ian-backed Hezbol­lah mil­i­tant group.