Global travel warnings after Iran

Saudi Arabia said Monday it was dealing with more drones and missile strikes as a slew of countries warned against travel to the kingdom due to fatal attacks on Riyadh's airport by Iran-backed Houthi militants.

The Australian and New Zealand governments on Monday cautioned their citizens against traveling to King Khalid International Airport in Riyadh and other Saudi destinations, joining similar advisories from the U.K., U.S., Canada, France, Germany, Japan and others.

It came as the Saudi aviation authority extended the suspension of operations at the airport, which has been hit by numerous projectiles over the past week. The deadliest strike came on Saturday, when 12 people were killed and more than 300 were injured, according to officials. Another strike on Sunday killed one person and injured nearly a dozen.

Yemen's Iran-backed Houthi rebels have claimed responsibility for the attacks, which have raised questions over the robustness of Saudi Arabia's defense capabilities despite its huge military spending.

The fatalities come as the kingdom hosts major corporate conferences, including the World ⁠Petroleum Congress, the International Energy Forum Ministerial Meeting and the Future Investment Initiative.

Airlines canceled hundreds of flights scheduled for the coming days, and about 100 flights were forced to divert to other airports, according to Flightradar24. The Federal Aviation Administration warned U.S. carriers of potential risks of flying over and around Saudi Arabia.

Delta Air Lines is scheduled to debut a nonstop flight from Atlanta to Riyadh on Oct. 23, but a spokeswoman said the carrier hasn't made a decision yet on whether to postpone the new route.

U.S. President Donald Trump said Sunday that the U.S. "may" join Saudi Arabia in its retaliation against the Houthis.

Iran's foreign minister, Abbas Araghchi. said Sunday that he had told Saudi Minister of Foreign Affairs Prince Faisal bin Farhan Al Saud by phone that Tehran was willing to take steps to start dialogue between Saudi Arabia and Yemen, where the Houthis are based.

Iranian Foreign Ministry spokesperson Esmail Baghaei meanwhile said Iran was still reviewing a U.S. response to its proposal for reopening the Strait of Hormuz and would reply through its intermediaries, Reuters reported.

— CNBC's Leslie Josephs contributed to this report.