Vietnamese low-cost airline VietJet may place a provisional order for as many as 100 Airbus medium-haul jets worth up to $10 billion, a source close to the airline said on Tuesday.

The deal could involve between 92 and 100 A320 or A321 aircraft and if confirmed, would be signed during a visit to Paris by Vietnam’s prime minister this week.

Talks are continuing and a deal has not yet been reached, sources familiar with the discussions said earlier on Tuesday.