Iran passed another night without U.S. airstrikes on Sunday, as Washington paused a war nearing its fifth month and reports emerged that concerns over dwindling munitions were restraining plans for further escalation.

The lull has revived hopes of a return to negotiations after nearly two weeks of consecutive nightly U.S. bombardments, although U.S. media reported the pause could also reflect pressure on stockpiles of Patriot interceptors and other defensive weapons.

Fighting over the strategic Strait of Hormuz derailed diplomatic efforts between Washington and Tehran, but the conflict then expanded beyond the vital energy corridor to include attacks on U.S. bases, regional shipping and Gulf allies.