France's President Emmanuel Macron and Jordan's King Abdullah II have in phone calls with all involved parties "expressed their utmost concern" and "emphasized the need to avoid a regional military escalation at all costs", writes AFP.
Jordan's Foreign Minister Ayman Safadi has also met his counterpart in Tehran with a message from the king. It is the first time in 20 years that Israel's neighbor Jordan has made a visit at such a high level in Iran.
The G7 countries' foreign ministers have also during a video conference on Sunday expressed strong concern and appealed to the parties to refrain from anything that could lead to new escalation.
"Be vigilant"
The Israeli army says that it is not currently changing its strategy regarding "protecting civilians", but urges all Israelis to be vigilant.
(Israel's) protection is not hermetic. Therefore, all citizens must be aware of the instructions, regardless of where they are, and be vigilant, said the military's spokesperson Daniel Hagari.
Israeli media writes that a potential Iranian attack could come as early as Monday, and refers to anonymous military sources. Jerusalem Post was the first with the information.
Israel is already prepared for any possible scenario, according to Prime Minister Benjamin Netanyahu.
Israel is already in a "multi-front war" with Iran and its proxies, said Netanyahu during a government meeting on Sunday.
Vowing revenge, Haniyah
Tensions in the region have increased this week, since Hamas leader Ismail Haniyah was killed in Iran just hours after Hizbollah's chief of staff Fuad Shukr was killed in an Israeli attack in Lebanon.
The Iranian regime and its allies, including terrorist-listed Hamas and Hizbollah, have vowed revenge. Israel, on its part, has warned its enemies that they will have to "pay a very high price" for any "aggression".
Israel and Hizbollah have almost daily exchanged fire across the border since the Gaza War began after terrorist-listed Hamas attacked Israel in October last year.