China has threatened to derail a multibillion-dollar deal for 10 Airbus superjumbo aircraft, escalating its protest against Europe’s plan to bring international airlines into an emissions trading scheme.

Hong Kong Airlines had been due to formally announce an order for 10 A380 aircraft at the Paris Air Show earlier this week, two industry executives familiar with the agreement said. At list prices, the deal would have been worth $3.8 billion.

However the deal was being held up because of Beijing’s anger over the emissions scheme, which starts in January.

“These are not the only orders taken hostage by the Chinese, [but] the A380s are the first,” said one executive, noting that Airbus had other deals with Chinese carriers in the pipeline.

Airbus has declined to comment.