Saudi Arabiainfo-icon advised its nationals to leave Lebanoninfo-icon, further fueling fears of a heated confrontation with Iraninfo-icon in a country long known for being a battleground for proxy wars in the Middle East.

Saudi citizens were also advised not to travelinfo-icon to Lebanon, the official Saudi Press Agency cited the foreign ministry statement as saying, five days after Lebanese Prime Minister Saad Hariri unexpectedly resigned in a speech from Saudi Arabia.

Lebanon is in the cross-hairs of the escalating tension between Sunni-led Saudi Arabia and Shiite-led Iran, who are on opposite ends of conflicts across the Middle East. Iran-backed Houthi rebels in Yemeninfo-icon launched a missileinfo-icon at the international airport in Riyadh -- an attack Saudi officials said could be an Iranian "act of warinfo-icon." That day, Lebanon's Prime Minister Saad Hariri -- a pro-Saudi politician -- abruptly resigned, issuing a statement in Riyadh blaming Iran for meddling in Lebanon's affairs via its proxy, Hezbollahinfo-icon.

Iran denied supplying Houthi fighters with missiles, and accused Saudi Arabia of trying to escalate tensions.

"The safety net Lebanon had is no longer in place," Sami Nader, head of the Beirut-based Levant Institute for Strategic Affairs, said by phone, adding that Lebanon may face the same kind of economic sanctions imposed by a Saudi-led alliance on Qatarinfo-icon since June. "We should expect further escalation from Saudi Arabia against Lebanon."

After Hariri's resignation, Saudi Arabia warned the Lebanese government of the dangers of Hezbollah, accusing the group -- which is part of the Lebanese government -- of being involved in every terrorist attack that threatens the kingdom. It has denied forcing Hariri to resign.