Israeli Defense Minister Yoav Gallant did say on Wednesday, however, that his country's war with Iran's so-called proxy groups in the region had entered a "new phase," announcing a shift to the north of Israel after 11 months of intense conflict with Hamas in the Gaza Strip.

The Hezbollah leader, Hassan Nasrallah, did not say how his group would respond to attacks on hand-held devices, which killed dozens when pagers and walkie-talkies exploded.

The absence of a full-blown war in Lebanon has been touted as a core U.S. achievement, but now Washington’s grip on the crisis appears more tenuous than ever.