PARIS (Reuters) - Russian cargo airline Volga-Dnepr Group has signed a memorandum of understanding to buy and lease a total of 20 more Boeing (>> Boeing Co) 747-freighters in what would be a major boost for the U.S. planemaker's struggling four-engined jumbo.

Both Boeing and European rival Airbus (>> Airbus Group) have seen orders for their biggest planes dry up as customers opt for improved twin-engined jets that can fly almost as far.

At Boeing, that has put a question mark over production of the 747, with analysts warning the company could face a $1 billion accounting charge if the programme was shut down.

The U.S. group has made a concerted push for freighter orders to keep production going.

If the deal with Volga-Dnepr is firmed up, the Russian company will take on the 20 planes over the next seven years, Boeing said at the Paris air show on Wednesday.

It did not say how many of the planes would be bought or how many leased. At list prices, the 20 jets would be worth around $7.4 billion.

Under the agreement, Volga-Dnepr will also provide its Antonov-124-100 aircraft for the transportation of aviation equipment for Boeing and its partners, Boeing said.

Volga-Dnepr took delivery of its first 747-8 freighter in 2012.

"For Volga-Dnepr Group, adding more 747-8 freighters will allow development of the group's scheduled business, AirBridgeCargo Airlines, and keep the airline's high growth rates," Boeing said.

(Reporting by Mark Potter; Editing by James Regan)

Stocks treated in this article : Airbus Group, Boeing Co