Western officials declined to give specifics on China’s drone programme but Bloomberg reported that Chinese factories are developing a drone called the Sunflower 200, similar in appearance to Iran’s Shahed.
Sunflowers are a national symbol of Ukraine.
As well as sending rifle sights and equipment to produce tanks to Russia, China has started sending satellite images of battlefields in Ukraine.
Julianne Smith, US ambassador to Nato, said this highlighted Beijing’s role as an ally of the Kremlin.
“Here at Nato, we’re making sure that we can expose the fact that China is no longer a neutral player,” she said.
Russia’s most important partner
Since Vladimir Putin launched his full-scale invasion of Ukraine in February 2022, China has become Russia’s most important trade partner.
Antony Blinken, the US secretary of state, last month accused China of keeping the “Russian defence industrial base going” by providing 70 per cent of its machine tools and 90 per cent of its microelectronics.
Russia now also sells most of its oil and gas to China at a discounted price, and Chinese banks provide critical infrastructure for Russia’s financial institutions to trade roubles for yuans.
On Wednesday, the head of Russia’s civilian nuclear power programme even said he was flying to China next week to start a joint project to build a nuclear power station on the Moon by 2036.