Vietnamese budget airline VietJet, famed for its bikini-clad air hostesses, has agreed to buy 100 passenger jets from US aircraft maker Boeing for $11.3 billion, the airline said Monday, in a deal signed in front of President Barack Obama in Hanoi.

In a statement, VietJet said the deal was "the largest ever single commercial airplane purchase in Vietnam aviation".

It was penned in front of Vietnamese President Tran Dai Quang and the American leader, who is on a three-day trip to the communist nation. 

A White House official confirmed the deal for 100 Boeing jets was among a raft of commercial agreements sealed on Monday worth more than $16 billion.

"We expect this will support 60,000 American manufacturing and technology jobs," the official added.

Founded in 2007 VietJet, which has previously drummed up publicity with bikini-wearing air stewardesses, is making a major move into the lucrative Southeast Asian aviation sector.

In February the carrier announced that it had signed a $3.04 billion deal with US engine maker Pratt & Whitney, underscoring the growth potential of the region's low-cost airline market.

Industry players have said that Southeast Asia, including Vietnam, is a key growth market for budget air travel, driven by a growing middle class, many of whom are travelling for the first time.

US aircraft maker Boeing has forecast that the region needs 3,750 new airplanes in the next 20 years, with more than three-quarters of the deliveries being single-aisle airplanes favoured by budget carriers.