OTTAWA -- The last conversation between Ukraine International Airlines Flight PS752 pilots and air traffic personnel on the ground in Tehran before the plane crashed minutes after take-off was nothing out of the norm, said Ukraine鈥檚 foreign affairs minister.

In an interview with CTV鈥檚 Question Period, airing Sunday, Vadym Prystaiko said all communication was "peaceful," supporting the assertion made by the U.S. and Canada that the flight was shot down by an Iranian missile, mistakenly or otherwise.

"What we have as of now is access to the recordings of the tower talking to our crew before something happened to the plane. The last conversation which we had recorded was peaceful," said Prystaiko, adding the pilots noted everything was "OK."

The former ambassador to Canada said Ukraine鈥檚 intelligence officials have seen the flight鈥檚 black boxes but still don't have access to their content to determine the cause of the crash.

"We鈥檝e seen the black boxes themselves, the equipment itself. I鈥檝e also seen pictures of our embassy people and our team standing next to them," he said.

The Ukrainian flight crashed near Iran鈥檚 capital on Wednesday morning, killing all 176 passengers and crew on board, including 57 Canadians. The crash occurred just hours after Iran launched air strikes against a military base in Iraq housing U.S. troops. 鈥� retaliation for the U.S. assassination of a high-ranking Iranian military general.

Iran has denied it is responsible for the plane crash and has asked the U.S. and Canada to show evidence of their claims.

Prystaiko said the problem lies with accessing the essential information within the black boxes to help determine what happened in the minutes before the plane set ablaze.

"As of now we don鈥檛 have access to this but Iranians are co-operating and we hope that we鈥檒l be able to check that this information was intact," said Prystaiko.

"We insist that these black boxes be given to Ukraine authorities. We will transfer them to Kyiv and they鈥檒l be investigated with the help of all our international partners."

While Ukraine is entertaining all possible explanations for the crash, Prystaiko said there is strong evidence to believe that an Iranian surface-to-air missile is the cause.

"We believe there is enough to take very serious consideration of this scenario," he said. "It鈥檚 at the top of our list."

As of now, Ukraine is in the process of reconstructing the plane with key body parts its investigators hadn鈥檛 had access to before.

"We鈥檝e insisted that the local police clear the ground. At least we have the remnants of people and the plane respected and left untouched," he said. "We were missing very particular pieces of the plane; now most of them are in our possession."

Extracting, analyzing and sharing intelligence with relevant international counterparts will be Ukraine鈥檚 next steps, Prystaiko added.

Ukraine has been given the green light by Iran to include Canadian representatives in their investigation on the ground.

In a separate interview airing Sunday, former public safety minister Ralph Goodale said it鈥檚 imperative Canada maintain close ties with Ukraine throughout this process.

"It鈥檚 very good that we have a longstanding, good relationship with Ukraine," he noted. "We need to have every bit of leverage we can get working with other countries to get to the truth here."

Both countries aren鈥檛 ruling out the possibility of imposing economic sanctions on Iran, as the U.S. has done, should evidence indeed prove an Iranian surface-to-air missile was employed to take down the aircraft.

The U.S. sanctions are strictly related to Iran鈥檚 retaliation for the killing of Gen. Qasem Soleimani.

In an interview airing on CTV鈥檚 Question Period Sunday, Transport Minister Marc Garneau said Canada would have 鈥減referred to be warned ahead of time鈥� about the Americans鈥� planned strike on Soleimani at Baghdad International Airport on Jan. 3.

"We're a strong ally of the United States and we'll continue to be a strong ally, but I believe that we have indicated it would have been our preference to be alerted to this,鈥� he said.