France on Friday warned its citizens to "imperatively refrain from travel in the coming days to Iran, Lebanon, Israel and the Palestinian territories", the foreign minister's entourage told AFP.
Foreign Minister Stephane Sejourne issued the recommendation after Iran threatened reprisals over an Israeli strike on the Iranian consulate in Syria, sparking fears of an escalation of violence in the Middle East.
Later, Poland's foreign ministry advised against travel to Israel, Palestine and Lebanon, it said in updated travel guidance published on Friday.
"It cannot be ruled out that there will be a sudden escalation of military operations, which would cause significant difficulties in leaving these three countries," the ministry said in a statement.
"Any escalation may lead to significant restrictions in air traffic and the inability to cross land border crossings."
The Israeli-occupied Palestinian territories consist of the Gaza Strip and the West Bank.