Canada’s foreign minister Francois Phillipe Champagne who is in Ukraine said on Wednesday that Iran must give access to the black boxes from the Ukrainian airliner which was shot down by an Iranian missile in early January. “We do expect and we demand… from Iran to give access to the black boxes without any further delay,” Champagne said during a press conference with his Ukrainian counterpart Vadym Prystaiko in Kiev.

Champagne stressed that it has been more than 30 days since the accident killing all 176 onboard and that Iran will “undermine the international law” if it chooses to keep the recorders. “We have questions and we expect Iran to provide answers,” the minister said.

“We hope that Iran will choose the way of transparency.” The Kiev-bound Ukraine International Airlines Boeing 737 crashed shortly after taking off from Tehran on January 8.

Tehran admitted several days later it had accidentally shot down the airliner during a confrontation with the United States. Iran had launched missiles at US forces in Iraq in response to the killing of top general Qasem Soleimani on January 3.

The victims were mostly Iranian and Canadian citizens, as well as a Ukrainian crew. Ukraine and Canada have repeatedly pressed Tehran to hand over the black box flight recorders to Kiev or Paris, but they remain in Iran.

Ukraine had demanded that Iran punish those guilty for the downing of the airliner and compensate the victims. Iran’s Prime Minister Hassan Rouhani had tweeted that the country ‘deeply regrets’ the ‘disastrous mistake.’

On January 12, Iranian President Hassan Rouhani promised a further investigation into the circumstances surrounding the plane crash while having a telephonic conversation with Canadian Prime Minister Justin Trudeau.