Russia\'s second-largest airline Transaero signed a $1.7 billion deal Thursday to buy four Airbus A380 jets, becoming the first ex-Soviet region carrier to order the world\'s biggest passenger jet. Transaero\'s general director Olga Pleshakova and Airbus Executive Vice-President Europe, Christopher Buckley, signed purchase agreement on the first day of the annual Saint Petersburg Economic Forum. \"It is a historic moment for Airbus and this is the first contract in Russia and the CIS for the A380,\" Buckley told journalists at the signing, referring to the Commonwealth of Independent States, an alliance of ex-Soviet states. \"We are very confident that the fleet will not stop at four aircraft and we are looking forward to working towards (adding) many more A380s to this first in Russia.\" The A380, which entered service in 2007, is the world\'s biggest passenger jet and a key product in Airbus\'s line-up as it battles its main rival, US giant Boeing, for the top spot in the world civil airliner industry. The Transaero order is the first from an airline in Russia, the CIS and Eastern Europe and brings the total number of orders for the aircraft to 257 from 20 customers, Airbus said in a statement on its website. So far Airbus has delivered 77 of the planes. Transaero has until now almost exclusively used Boeing jets, but recently made a shift towards France-based Airbus, which is owned by European aerospace giant EADS. In December it signed a firm order with Airbus to buy eight smaller A320neo planes with the option of acquiring four more jets. \"It was really fairly significant what we did last year when we completed our first deal for new aircraft with Transaero,\" said Buckley. \"We have now broken into the Transaero market. They have now selected two of our aircraft (...) so we think we have quite a promising future ahead,\" he added. The A380 jets are due to be delivered starting in 2015 and are set to be used for longhaul flights between Moscow and southeastern Asia and the Caribbean region, Transaero\'s Pleshakova said. Transaero also signed a firm contract on Thursday at the economic forum to buy six Sukhoi Superjet-100 planes with the option of buying 10 more. The catalogue price of the planes in the firm contract is $212.4 million, with deliveries planned from 2015 to 2017, Transaero and Sukhoi Civil Aircraft said in a joint statement. The Sukhoi Superjet-100 produced by Russia\'s Sukhoi in partnership with Italy\'s Alenia Aermacchi was designed to revive the Russian aviation industry but its image was tarnished when a plane giving a demonstration in Indonesia crashed in May, killing 45 with the cause still under investigation. Transaero, which made its first flight in 1991 has a fleet of 86 planes and flies to more than 130 destinations. Its larger rival, former Soviet flag-carrier Aeroflot has a fleet of 120 planes, including both Airbus and Boeings as well as Sukhoi Superjet-100s.