A U.S. official says Iran could be about to fire missiles at Israel, as Israel announces "limited, localized" operations against Hezbollah in Lebanon.

Israel’s invasion of southern Lebanon comes after over a week of intense air strikes targeting Hezbollah’s strongholds in the country. Southern Lebanon has been most affected, with strikes also targeting the eastern Bekaa Valley and in the southern suburbs of Beirut.

Israel says it is operating in Lebanese border areas to dismantle infrastructure belonging to the militant group.

Israeli ground forces crossed into southern Lebanon, marking a significant escalation of an offensive against Hezbollah militants and opening a new front in the war.

Israel's widely expected ground invasion of Lebanon appeared to be getting underway early on Tuesday as its military said troops had begun 'limited' raids against Hezbollah targets in the border area.

The Israeli military said it was carrying out “targeted ground raids” in villages close to the Israeli border.

However, BBC state department correspondent Tom Bateman says the Israeli decision to escalate sharply the conflict with Hezbollah struck a potentially fatal blow to his entire strategy of the last 11 months - to try to stop the war in Gaza engulfing the region.