Ukraine on Sunday accused Iran's government of knowing immediately that it shot down a Ukrainian passenger jet last month despite denying responsibility for days.

According to Reuters, Ukrainian President Volodymyr Zelensky cited a leaked audio recording of an Iran Aseman Airlines pilot communicating with air-traffic control in Tehran. The pilot apparently informed the control tower that he saw "the light of a missile" and an "explosion" as the tower tried to contact Ukraine International Airlines Flight 752.

Zelensky said in a television interview that the recording "proves that the Iranian side knew from the start that our plane had been hit by a missile."

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Iranian officials knew their military had shot down a passenger jet and lied about it for days, Ukraine said Sunday, citing a leaked audio recording of an Iranian pilot communicating with air-traffic control in the capital Tehran.

In the leaked audio recording — said to be from the night in January when Ukraine International Airlines Flight 752 was shot down — a pilot for Iran Aseman Airlines radioed the air-traffic control tower to say he saw the "light of a missile," Reuters reports.

The control tower can reportedly be heard trying, unsuccessfully, to reach the Ukrainian passenger aircraft on the radio as the Iranian pilot says he saw "an explosion."

Aseman Flight 3768 was close enough to the airport in Tehran to see the blast, the Associated Press reported, citing publicly available flight-tracking data.

Ukrainian President Volodymyr Zelensky said in a television interview that the recording "proves that the Iranian side knew from the start that our plane had been hit by a missile."

Ukraine International Airlines said, according to Reuters, that the audio was "yet more proof that the UIA airplane was shot down with a missile, and there were no restrictions or warnings from dispatchers of any risk to flights of civilian aircraft in the vicinity of the airport."

UIA Flight 752 was flying from Tehran to the Ukrainian capital, Kyiv, on January 8 when it was shot down shortly after takeoff, killing all 176 people on board. The incident happened just hours after Iran launched a barrage of ballistic missiles at US forces in Iraq in retaliation for a US drone strike that killed Iranian Maj. Gen. Qassem Soleimani, and the country's air-defense systems were on high alert.

Iran initially said the aircraft crashed as the result of a mechanical error, but reports quickly began surfacing in the US, Canada, and parts of Europe that intelligence suggested the plane was shot down by a surface-to-air missile. Iran vehemently denied the accusations.

On January 11, however, Iran acknowledged that it accidentally shot down the commercial airliner.

Though it blamed "human error," Iran also sought to cast responsibility with the US, arguing that the killing of Soleimani had led to a dangerous spike in tensions that resulted in the accident. Still, Iranian citizens and international observers questioned why Iran didn't ground civilian air traffic after its missile attack on US-occupied bases in Iraq.

Iran said it mistook the airliner for an enemy missile. Iranian President Hassan Rouhani called the incident a "grave tragedy" and an "unforgivable mistake."

Iran's Civil Aviation Organization is in charge of investigating aviation incidents, with one official saying Ukraine's decision to release the confidential recording, which aired on Ukrainian television, had "led to us not sharing any more information with them."