Fears have emerged that heightened tensions between Iran and the United States could hamper investigations into a Ukrainian airliner that crashed in the outskirts of the Iranian capital.

Ukraine International Airlines Flight 752 crashed less than three minutes after taking off from Tehran's Imam Khomeini International Airport on Wednesday, killing all 176 people on board.

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The rules on probes into air crashes are set down in the 1944 Chicago Convention on International Civil Aviation, and the responsibility for the investigations is assigned to the countries where they occur.

This puts Iran in charge of the investigation, but the country that manufactures the aircraft and the one that operates the airline are also supposed to have representatives involved in such a probe.

However, Tehran has already indicated it will not hand over the recovered flight recorders - commonly known as black boxes - to the US for any probe.

Flowers and candles begin to pile up at a memorial to the flight crew at Boryspil International Airport near Kyiv, Ukraine [Valentyn Ogirenko/Reuters]

In theory, this means that the US National Transportation Safety Board (NTSB), which is the body charged with investigating air accidents, would be involved. The aeroplane's manufacturer, Boeing, is based in the US, and investigators would likely rely on experts from the manufacturer.

"That could be a little complicated," said Jean-Paul Troadec, former head of France's BEA airline safety agency.

The crash came on the same day that US-Iran tensions hit new heights as Iran fired a volley of missiles at Iraqi bases housing troops from the US and other foreign countries. It was the Islamic Republic's first physical response since the US killed top Iranian general Qassem Soleimani on Friday.

Boeing said that it was in contact with Ukraine International Airlines and that it was "ready to assist in any way needed".

This is a tragic event and our heartfelt thoughts are with the crew, passengers, and their families. We are in contact with our airline customer and stand by them in this difficult time. We are ready to assist in any way needed. pic.twitter.com/TsTlyY34Vd — The Boeing Company (@Boeing) January 8, 2020

However, the head of Iran's Civil Aviation Organisation, Ali Abedzadeh, said while the Ukrainians were free to participate in the investigation into the crash, "we will not give the black boxes to the manufacturer [Boeing] and the Americans," according to Iran's Mehr news agency.

An NTSB spokesman told the AFP news agency that the group was tracking developments and would follow normal procedures regarding international accidents.

The NTSB was also in contact with the US Department of State to determine the best way to proceed with respect to Iran, the spokesman said.

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In Washington, Secretary of State Mike Pompeo said in a statement: "The United States calls for complete cooperation with any investigation into the cause of the crash."

Reading information from the cockpit voice recorder and flight data is not in itself difficult, according to Troadec.

"The difficulty is if the recorders are in a very poor condition, then you need labs which have the experience and equipment [in recovering data]," he said.

Besides the NTSB, Troadec said the BAE and its counterparts in the United Kingdom and Germany have the knowledge to handle data recovery in such situations, as may Russia.

The BEA said it had yet to receive any request for assistance from the Ukrainian authorities.

The Chicago Convention also allows a country to let another country take charge of an investigation.

Dutch authorities carried out the investigations into the 2014 crash of a Malaysia Airlines plane in Ukraine. The flight was returning from Amsterdam when it crashed, killing 298 people including 193 Dutch nationals.