The comment by Boeing's biggest customer may put pressure on the aircraft maker to speed development of a revamped 777, provisionally called the 777X. Boeing has not yet offered the 777X for sale, though carriers such as Emirates and British Airways (ICAG.L) have been planning for it to enter service by the end of this decade.

Boeing appears to be at least a year away from offering a new version of the 777, Reuters reported this week, quoting people familiar with talks between the plane maker and its customers.

"If the aircraft meets our needs, Emirates would consider it as a replacement for our fleet of 175 current and ordered Boeing 777s, but we have no plans to place any orders at this time," Tim Clark told Reuters in an emailed statement.

He added: "Boeing has not yet approved the next generation of the 777-300ER which is not slated to be available until 2019-20."

Emirates has been pressing for the 777X to come out sooner rather than later. The 777 is one of the most successful jets of all time in terms of sales, and airlines are eager for a version that can go farther on less fuel with more passengers.

Clark was quoted as saying in an interview with Dubai-based Arabian Business magazine, published earlier on Thursday: "If it's as good as we hope it'll be, it's a natural thing to say 'yes we would probably roll over what we have to what they're offering with the new aircraft'."

The magazine also quoted him as saying: "We have been trying to get Boeing to build the 777-9x and 8x and we are working closely with them to try and persuade them that it's a good idea to build it. We are not there yet.

"I guess if they had been there we would have done orders by now but they're not. The moment you read that Boeing are launching the new 777 you will probably find that Emirates is fairly close behind."

Emirates has said it will need to replace its old 777s from 2017, which is prompting the push for a new version.

Clark also told the magazine that rival planemaker Airbus' (EAD.PA) 350-1000 model was not attractive to Emirates at the moment, unless the plane was changed. The A350-1000 is due to enter service in 2017. (Reporting by Praveen Menon; Editing by Andrew Torchia and Mike Nesbit)

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