On the Iranian side, Foreign Minister Mohammad Javad Zarif told Iran's IRNA news agency in Beijing, where he was on an official visit, that "There will be no war because neither do we want a war, nor has anyone the idea or illusion it can confront Iran in the region".
The commander of Iran's powerful Islamic Revolutionary Guards Corps, General Hossein Salami, said his country isn't looking for war but isn't afraid of a confrontation, either.
Fears of armed conflict were already running high after the White House ordered warships and bombers to the Middle East earlier in May to counter an alleged, unexplained threat from Iran.
Iraqi military spokesman Brig. The U.S. has been a significant presence globally since World War II, and is seen as a buffer against China as a rising global power.
In April, the USA announced the end of exemptions it had granted to eight nations - China, India, Italy, Greece, Japan, South Korea, Taiwan and Turkey - to buy Iranian oil.
These incidents came amid growing tension in the region between Iran and the US. The US government has provided no proof the ships are carrying hidden missiles and other munitions and CNN has not reviewed the intelligence that has led to the US assessment.
Ministers from Gulf countries were to meet in Saudi Arabia later on Tuesday after Saudi Arabia called for an urgent meeting of the regional Gulf Cooperation Council and the Arab League to discuss escalating tensions in the Gulf.
Saudi Arabia and other Gulf countries are traditional allies of the U.S.
No one has claimed responsibility, but two U.S. government sources said last week that United States officials believed Iran had encouraged the Houthi group or Iraq-based Shi'ite militias to carry it out.
"The ball is in Iran's court and it is up to Iran to determine what its fate will be".
The Saudi crown prince spoke on the phone with US Secretary of State Mike Pompeo about efforts to enhance security in the region, the Saudi Press Agency reported. There was no immediate statement by the State Department about the call.
With Congress unlikely to grant Trump new authority to strike Iran under the current circumstances, and amid a campaign of "maximum pressure" against the regime in Tehran, media reports revealed that Trump administration sent strong signals that they will be ready to make an end run around lawmakers, using the 2001 authorization for the use of military force, if necessary.