Russia is unable to deliver vital defence supplies it had committed to India's military because of the war in Ukraine, the Indian Air Force (IAF) says.

New Delhi has been worried that Moscow's invasion of Ukraine in February 2022 could affect military supplies from India's largest source of defence equipment. The IAF statement is the first official confirmation of such shortfalls.

The IAF statement was made to a parliamentiary committee, which published it on its website on Tuesday. An IAF representative told the panel Russia had planned a "major delivery" this year that will not take place.

A spokesperson for the Russian Embassy in New Delhi said: "We don’t have information which may confirm the stated."

There was no immediate response from Rosoboronexport, which is the Russian government's weapons export arm.

The report does not mention specifics of the delivery.

The biggest ongoing delivery is the S-400 Triumf air defence system units India bought in 2018 for $5.4 billion. Three of these systems have been delivered and two more are awaited.

IAF also depends on Russia for spares for its Su-30MKI and MiG-29 fighter jets, the mainstay of the service branch.

Russia, and the Soviet Union before it, has been India’s main source of arms and defence equipment for decades.

Russia accounted for $8.5 billion of the $18.3 billion India has spent on arms imports since 2017, according to the latest data from the Stockholm International Peace Research Institute.

Over the past two decades, New Delhi has sought to reduce its dependence on Moscow and looked westward towards France, the United States and Israel.

It is also pushing Indian companies to produce more at home in collaboration with global players.

The IAF also informed the parliamentary panel that the Russia-Ukraine war affected its supplies so much that it slashed its projected capital expenditure on modernisation for the financial year ending March 31, 2024, by nearly a third compared to the previous fiscal year.

The air force had projected a capital expenditure of 853 billion rupees ($10.38 billion) for fiscal 2022-23 and cut it to 588 billion rupees ($7.15 billion) in the national budget presented in February.