The US interior department’s decision not to buy more drones with Chinese parts has made it more difficult to fight wildfires, according to an internal departmental memo, which lays bare one cost of the Trump administration’s crackdown on Chinese technology.

The memo, which was written by the department’s Office of Aviation Services earlier this year, found that by the end of the year, the department will have carried out only a quarter of the controlled burning it might otherwise have done had it gone ahead with planned drone purchases.

The US is experiencing one of its worst years for wildfire outbreaks thanks to hot weather and a lack of firefighters. And while none of those appear to have happened on federal land, government insiders warn the de facto ban on buying drones with Chinese components risks making the situation worse.