Countries in the Middle East have told European officials they are concerned about the risk of civil war in Iran as a result of the conflict between Tehran and the U.S. and Israel, EU Foreign Chief Kaja Kallas said Thursday.

"When we talk to the countries in the region, they are also worried about civil wars inside Iran because of the regime's leadership and what is going on there," she said ahead of a video conference with EU foreign ministers and representatives of the Gulf Cooperation Council on the situation in Iran and the broader Middle East.

The EU wants to push forward a diplomatic solution.

"Wars really end in diplomacy, and there has to be room for diplomacy here to really get out of this cycle of escalation," she told reporters.

The EU is "extremely worried" about maritime security in the region and that it is trying to keep routes such as the Strait of Hormuz open, she said, although since the EU was not dependent on oil from Gulf states, the attacks there did not have a large short-term impact on the security of the supply of oil to the EU.

The conflict has also escalated a dispute between the U.S. and Spain, with Washington threatening to cut trade with Madrid over Spain's refusal to allow U.S. aircraft to use jointly operated naval and air bases in southern Spain for the offensive against Tehran.

Spain has denounced the U.S. and Israeli bombings of Iran as reckless and illegal. The White House said on Wednesday Spain agreed to cooperate, but Madrid has denied this.

Asked about the spat, Kallas said she hoped Washington would respect the trade agreement reached last year that applies to all EU member states.