One slap not enough: Iran

Tehran: Iran has finally launched what it promised would be a 'crushing revenge' strike against the US over the death of General Soleimani - but succeeded only in damaging two airbases in neighboring Iraq.

The country's Islamic Revolutionary Guard Corps fired 22 ballistic missiles at the Ain al-Asad airbase in western Iraq and Erbil International airport in the north in the early hours of Wednesday, but failed to kill a single US or Iraqi solider.

The attacks mark a significant escalation of tit-for-tat blows exchanged between the US, Iran and their allies since last summer - but falls far short of fatal strikes on commanders and troops that had been feared.

Ayatollah Ali Khamenei, speaking on Iranian TV shortly after the missiles were launched, described the strikes as 'a slap' and said they are 'are not sufficient (for revenge)'.

Iran's aviation authority said it would not hand over to Americans the recovered black boxes of a Boeing 737 that crashed on Wednesday, killing all 176 passengers and crew.

"We will not give the black boxes to the manufacturer (Boeing) and the Americans," Iran Civil Aviation Organisation head Ali Abedzadeh said, quoted by Mehr news agency.

"It's not yet clear which country the black box will go to for the investigation," he added.

Following the crash of Ukraine International Airlines flight PS752 shortly after takeoff from Tehran on Wednesday, Iran said it had recovered the Boeing 737's two black boxes.

Abedzadeh said that based on global aviation rules, it was the right of the country where air crashes occur to carry out the investigation.

"This accident will be investigated by Iran's aviation organisation but the Ukrainians can also be present during the incident's investigation," he added.

Under the rules of the International Civil Aviation Organisation, of which Iran, Ukraine and the United States are all members, air crash investigations are led by the country where the accident occurred.

However, according to aviation experts, the countries that are capable of analysing black boxes are few -- notably Britain, France, Germany and the United States.

France's Accident Investigation Bureau (BEA), which handles air crash investigations, said it had not received any request for help from the Iranian authorities after Wednesday's crash.

The United States's Federal Aviation Administration has said it would ban US carriers from operating in the airspace over Iraq, Iran and the Gulf of Oman, as well as the waters between Iran and Saudi Arabia, after Iran launched a missile attack on US-led forces in Iraq.

Aviation regulator DGCA asked Indian airlines to remain vigilant and take all precautions in airspace over Iran, Iraq, Gulf of Oman and waters of Persian Gulf, hours after a Ukrainian plane carrying 176 people crashed near Tehran in Iran.

A meeting was called and the airlines were "sensitised", a senior official of the Directorate General of Civil Aviation (DGCA) said.