Indonesia's Kartika Airlines is negotiating leasing and possible financial support arrangements for the Sukhoi Superjet 100s it first agreed to acquire in 2008.
Sukhoi insists the talks are being conducted despite indications from the region that the deal has collapsed.
Kartika initially committed to 15 Superjets, plus 15 options, in 2008 and firmed the deal in 2010. But Sukhoi says a further contract, covering the 30 aircraft, was signed in 2012.
"Depending of the results of the negotiations the exact delivery time of the 30 [Superjets] will be announced," says Sukhoi's civil aircraft division.
While Sukhoi says the exact delivery time "was not determined" when the latest contract was sealed, the 2008 disclosure projected that the airline would receive the twinjets in 2011.
Sukhoi says it is "currently negotiating about leasing and financial support" with Kartika, although a recent report, citing one of the airframer's regional directors, said Sukhoi had withdrawn from the deal over doubts about Kartika's financial position.
Kartika could not immediately be reached for comment. Sukhoi had counted 30 Superjets for Kartika among its firm backlog for the type.