The Turkish government and the country’s largest defense company are under increasing pressure from Turkey’s NATO allies to rethink a September decision to award a $3.44 billion air defense contract to a Chinese bidder.

Procurement officials have privately admitted that if Turkey finalizes the deal with the Chinese manufacturer, its entire defense cooperation effort with Western counterparts, including defense and non-defense companies, could be jeopardized.

“I think there is growing concern in Ankara over that deal,” one official familiar with the program said. “These concerns will definitely play a role in final decision-making, although they alone cannot be a reason to change course.”