India and Russia signed a deal in 2015 under Indian Prime Minister Narendra Modi's 'Make in India' programme for the supply of 200 Russian KA 226T helicopters, with Russia to deliver 60 and the remaining to be assembled and manufactured in India.
The two countries also have held preliminary talks for the supply of over 100 of the KA 226-T helicopters for the Indian Navy, Boginsky said.
"We have done significant successful work and provided all information to India's ministry of defence, unfortunately there is no efficient and quick way from the Indian side," he told Reuters at the Dubai Air Show.
"We can't understand the reasons for the delay."
On the order for the Indian Navy, Boginsky said India would benefit from combining both orders to gain more value in enhancing its capabilities.
"The main winner will be India if both orders are joined," he said, adding Russian Helicopters was awaiting a formal request of an order from the Indian Navy.
Civilian helicopters account for about 30-35% of Russian Helicopters' total sales while the remaining 65-70% are military choppers. The civilian-military sales ratio is expected to remain the same in the next three years but total sales volumes could increase as Russian Helicopters brings to the market its expanded range of choppers, said Boginsky.
The company is in talks with international customers including some in the Middle East for sale of its new Mi-38 helicopters, he said, declining to elaborate.