Japan is urging its citizens to leave Lebanon and has decided to prepare military flights for their possible evacuation, the government said Friday.

Israeli bombing has killed hundreds of people this week in Lebanon, particularly in Hezbollah strongholds while the militant group has retaliated with rocket barrages.

"We're currently checking the safety of Japanese citizens living in Lebanon, as well as urging them to leave the country while regular commercial flights remain in operation," Chief Cabinet Secretary Yoshimasa Hayashi said Friday morning.

Hours later, the Defense Ministry said Air Self-Defense Force planes had been ordered to go to Jordan and Greece to be on standby in case Japanese nationals need to be transported out of the region.

The C-2 transport aircraft would be used to evacuate around 50 Japanese citizens currently in Lebanon, media outlets including Kyodo News said, citing unnamed government sources.

Foreign Minister Yoko Kamikawa said Wednesday that Tokyo is "strongly concerned about the escalation of tensions between Israel and Hezbollah."

Japan, she added, "strongly urges" all parties to "exercise the utmost restraint to avoid further escalation."

Israel has rejected a push by allies for a 21-day cease-fire in Lebanon and has vowed to keep fighting Hezbollah militants.