Volga-Dnepr Airlines (VI, Ulyanovsk Vostochny) has sent a formal notice to the Canadian government demanding the return of an An-124-100 grounded at Toronto Pearson, and will resort to international arbitration if the matter is not resolved in the next six months, the Interfax news agency has reported.

The Russian cargo specialist invoked the 1989 Russia-Canada bilateral investment treaty, Article IX of which gives any disgruntled investor the right to an international arbitration tribunal six months after a formal notice of the dispute has been issued.

"Volga-Dnepr remains open to negotiations with Canadian representatives to resolve the issue and return the aircraft," the airline said.

"The Government of Canada is assessing the letter. We will continue to defend the interests of Canadians," a government spokesperson told public broadcaster CBC.

RA-82078 (msn 9773054559153) has been grounded at Toronto Pearson airport since February 27, 2022, when Volga-Dnepr Airlines operated a commercial charter from China to Canada carrying COVID-19 tests procured by the Canadian government. However, once Canada joined the European Union and the United States in sanctioning Russia for its full-scale invasion of Ukraine, launched on February 24, the freighter was prevented from departing. In mid-April 2023, Canada specifically designated Volga-Dnepr Group. Ottawa said it was contemplating ways to transfer the aircraft to Ukraine, where it could be used to support humanitarian relief and defence against the Russian invasion. However, due to the legal complexity of the process, the aircraft has yet to be seized. For now, it remains Volga-Dnepr's property.

The Russian Foreign Ministry called Canada's actions "cynical theft".

Privately-owned Volga-Dnepr Airlines operates eight more An-124-100s and one An-124-100-150 - all of them currently stored. The Antonov Design Bureau quadjets were manufactured exclusively in Ukraine, and Kyiv has long argued that the Volga-Dnepr Group and Russian military operators of the type were conducting unauthorised and thus unsafe maintenance of the freighters.