Hamid Abutalebi, Iran's proposed UN ambassador, gestures in this undated handout photo. [Photo/Agencies]

TEHRAN -- The spokesman for Iran's mission to the UN said the US decision to deny a visa for an Iranian newly-proposed ambassador to the UN is "regrettable," local media reported on Saturday.

The US decision to deny visa to Hamid Aboutalebi is "unwise and obvious violation of international law," semi-official ISNA news agency quoted Hamid Babaei as saying in a statement.

Also, "the US decision contradicts the obligation of the host country vis-a-vis the United Nations," the Iranian official said, adding that the US move undermines the authority of the independent countries in appointing their own missionary to the UN.

"The Islamic republic is entitled to do any necessary diplomatic measure to protest this illegal action," the announcement was quoted as saying.

Also on Saturday, an Iranian Foreign Ministry official said that Iran does not have any replacement for its newly-proposed UN ambassador who has been denied entry visa by the United States.

"We do not have a replacement for Hamid Aboutalebi and we will pursue the issue through the available legal mechanisms in the United Nations," Iranian deputy foreign minister for legal affairs Abbas Araqchi was quoted as saying by official IRNA news agency.

"Based on the agreements, the host country of the UN office should fulfill its international obligations," said Araqchi.

On Friday, the Whited House said the United States has informed Iran that it would not grant a visa to its newly appointed UN ambassador Hamid Aboutalebi, a member of the group responsible for the 1979 takeover of the US Embassy in Tehran.

US House of Representatives passed Thursday legislation by unanimous consent that would ban Aboutalebi from entering the United States. The vote came after the Senate passed a companion bill on Monday.

Lawmakers sponsoring the bill said Aboutalebi should be banned from entry to the United States because he was a member of the militant group that held 52 Americans hostage when it seized the US embassy in Tehran in 1979.

In the meantime, the UN hoped that the visa denial incident between the United States and Iran would "be resolved bilaterally, " a UN spokesman said on Friday.

The UN had not been officially approached concerning this matter, UN spokesperson Stephane Dujarric said, noting that the Host Country Agreement was a public document which clearly lays out responsibilities.

According to the agreement, as host country for the UN, the United States, must provide rights to persons invited to the New York headquarters.

The Iranian Foreign Ministry has slammed the US stance on the new ambassador as "unacceptable."