WASHINGTON -  Qatar Airways announced a large airplane order with Boeing late Friday that includes up to $6.9 billion in single-aisle planes following delays in a rival Airbus offering.

Under the agreement, Qatar will buy 30 new-generation Boeing 787s and 10 Boeing 777s, both widebody aircraft, for $11.7 billion, the companies announced.

Qatar Airways also signed a letter of intent to purchase up to 60 narrow-body Boeing 737 aircraft. The deal is worth as much as $18.6 billion all together.

The order for the 737s follows unusual public criticism of Airbus earlier this year by Qatar Airways chief executive Akbar Al-Baker over delays in deliveries of the single-aisle Airbus A320neo due to problems with its engine. The order would help meet growing demand for air travel, Al-Baker said Friday.

But the decision to go with Boeing was also prompted by "ongoing issues" with Boeing rival Airbus, Al-Baker acknowledged, appearing with Boeing executives and US and Qatar government officials at a news conference in Washington.

"Boeing has started building airplanes before everybody else," he said. "They make the best airplanes, even if their competitors will not like me saying this."

Al-Baker later emphasized that his company would continue to work with Airbus and take delivery of the A320 planes when they are ready.

We are not "pointing fingers or trying to embarrass Airbus," he told AFP. "We have close relations with Airbus and we are continuing to receive aircraft orders." "The decision for us to buy Boeing airplanes is to get them for certain missions which today Airbus aircraft are not able to do," he added. "We will maintain all of our commitments to Airbus."

The contract for the 737 marks the first time Qatar Airways has ordered single-aisle planes from Boeing in more than 15 years, the companies said.

Al-Baker threatened to cancel the Airbus order in April due to problems with the engine and other difficulties, resulting in an "unacceptable" delay in delivering six planes. "We always in Qatar Airways have a plan B," he said at the time.

Qatar Airways cancelled an order for one of the Airbus planes in June.

The Qatar contract gives Boeing a boost. The US company had net orders of 380 through the end of the third quarter, suggesting its full-year tally for 2016 will come in below last year's 868.

"Our partnership with Qatar Airways has grown and strengthened tremendously over the years and I look forward to the time when its fleet will feature an increasing number of both our single and twin-aisle airplanes," said Ray Conner, chief executive of Boeing's commercial airplane division.

The companies did not release a timeframe for deliveries.

Shares of Boeing fell 0.7 percent to $133.53 in afternoon trade.