Iran's Foreign Minister Mohammad Javad Zarif on Tuesday said the US declined to issue him a visa to attend a United Nations meetings in New York amid the tensions sparked by an American drone strike killing a top Iranian general.

Speaking in Tehran, Zarif said: "They fear that someone comes to the US and reveals realities."

The move was criticised by Beijing and Chinese foreign ministry spokesman Geng Shuang said that the US has an international obligation to issue visas for such meetings as the host country of the UN.

Geng also said China is highly concerned about the situation in the Middle East and urged the US not to abuse the use of force. He called on all parties to exercise restraint to prevent a spiral of escalation.

The US State Department has not commented on Zarifs visa request. The US as the host of the UN headquarters is supposed to allow foreign officials to attend such meetings.

Under the 1947 UN "headquarters agreement," the United States is generally required to allow access to the United Nations for foreign diplomats. But Washington says it can deny visas for "security, terrorism and foreign policy" reasons.

Earlier, a US official had said the US had not allowed Zarif to attend a UN Security Council meeting in New York on Thursday.

Iran's mission to the United Nations had said: "We have seen the media reports, but we have not received any official communication from either the US or the UN regarding Foreign Minister Zarif's visa."

Meanwhile, UN spokesman Stephane Dujarric declined to comment on the US denial of a visa for Zarif.

Zarif wanted to attend a meeting of the Security Council on Thursday on the topic of upholding the UN Charter.

The meeting and Zarif's travel had been planned before the latest flare-up in tensions between Washington and Tehran.

The Security Council meeting would have given Zarif a global spotlight to publicly criticise the United States for killing Soleimani.

Iran's UN envoy, Majid Takht Ravanchi, has described the killing of Soleimani as "an obvious example of State terrorism and, as a criminal act, constitutes a gross violation of the fundamental principles of international law, including, in particular [...] the Charter of the United Nations".

Zarif last travelled to New York in September for the annual gathering of world leaders at the United Nations — after the United States sanctioned him for implementing "the reckless agenda of Iran's Supreme Leader".

The sanctions block any property or interests Zarif has in the United States, but he said he had none.

Zarif also attended UN meetings in April and July. During his July visit, Washington imposed tight travel restrictions on Zarif and diplomats at Iran's mission to the United Nations, confining them to a small section of New York City.

UN Secretary-General Antonio Guterres spoke with US Secretary of State Mike Pompeo earlier on Monday. State Department spokeswoman Morgan Ortagus said in a statement the pair discussed events in the Middle East and that Pompeo "expressed his appreciation" for Guterres' diplomatic efforts.