As part of this plan, the company is expected to seek approval from its board of directors as soon as next month to sell its new variant known as the 777X, according to the sources familiar with the matter.
The aeroplane manufacturer has already made conditional offers to at least three airlines including Emirates; International Consolidated Airlines, the parent company of Iberia and British Airways; and Japan Airlines to become launch customers for the new jetliner.
The new version is being designed to compete with Airbus A350, which has a seating capacity of between 270 and 350 and is expected to be launched in mid-2014.
Boeing spokesman Marc Birtel was quoted by the Wall Street Journal as saying that although the timeline for the 777X has not been set, the company may launch the jetliner around the end of the decade.
The company is going ahead according to the programme schedule and is working with the customers on their requirements for the airliner, Birtel added.
The extended twin jet aeroplane series will include a 777-9X, which will accommodate about 400 passengers and is scheduled for delivery in late 2019, while the 777-8X, which will be a replacement of the 777-300ER, is slated for launch in 2021 and will seat up to 350 passengers.
Boeing has been in discussions to make a final decision on whether to use engines from both General Electric and Rolls-Royce to power the new versions of 777 jets; it is expected to select GE as the sole supplier for the programme.
The new jetliners are likely to feature a new flight deck with larger displays and carbon-fibre composite wing, which will be a scaled-up version of that used by the 787 Dreamliner.
Image: The new versions of Boeing 777 are tentatively designated as 777-8X and 777-9X. Photo: courtesy of Boeing.