Kuwait could buy a single Boeing C-17 and a support package worth $693 million, the US government announced on 27 September.
The possible deal would give Boeing its eighth customer for the airlifter and extend the C-17 production line by about five weeks.
Boeing executives have long discussed Kuwait as a potential C-17 buyer, but the US Defense Security Cooperation Agency formally informed lawmakers about the possible transaction on 24 September.
The Kuwaiti air force needs a strategic airlifter for "relief support, humanitarian disaster and peacekeeping missions, as well as transporting dignitaries and cultural assets to various regional and international destinations", the DSCA notice says.
© Staff Sgt Mike Meares/US Air Force
Boeing is also negotiating with India to buy 10 C-17s, with a contract signing possibly to coincide with President Barack Obama's planned visit to New Delhi in November.
The UK government is also interested in buying an eighth C-17, although the funding will be decided based on the outcome of its ongoing Strategic Defence and Security Review.
Further C-17 sales are also being proposed to other countries in the Middle East and Europe, and to South Africa.
However, Boeing says a production gap is still possible, given the slow process of closing military aircraft deals on the foreign market. The company is currently scheduled to deliver the last C-17 in September 2012.
The US Air Force has not asked for new C-17s in four years, but Congress has inserted funds to buy 43 more aircraft during that period. This year, the Air National Guard has listed a need for five C-17s worth $1.3 billion on its list of unfunded priorities.
In July, Senator John McCain warned that the Senate Appropriations Committee may consider adding more C-17s to the US defence budget in fiscal year 2011. The issue is likely to remain unresolved until after the Congressional elections in November.