Businessman Spavor, who worked with North Korea, and former diplomat Kovrig were picked up in early December, shortly after Canada arrested Huawei Technologies chief financial officer Meng Wanzhou, who faces extradition to the United States.
China has repeatedly demanded Meng be released, and reacted angrily last week when Canada’s government approved extradition proceedings against her.
In a short statement on its microblog, the ruling Communist Party’s Central Political and Legal Affairs Commission said Kovrig had often entered China using an ordinary passport and business visas “stealing and spying on sensitive Chinese information and intelligence via a contact in China”.
“Spavor was Kovrig’s main contact and provided him with intelligence,” the commission added, without giving details.
Kovrig severely violated Chinese laws, and China will start the next judicial proceedings in due course, it said.
“China is a country with rule of law and will firmly crack down on criminal acts that severely undermine national security.”
While Canada says China has made no specific link between the detentions and Meng’s arrest, experts and former diplomats say they have no doubt it is using the cases of the two men to pressure Canada.
Kovrig works for the International Crisis Group (ICG), which focuses on conflict resolution and has denied any involvement in espionage.
Canadian diplomats have been allowed to see the two men. However, sources familiar with the case have said Kovrig has not been allowed access to lawyers or family members, unlike Huawei’s Meng.
It is not clear what conditions Spavor is being held in.
China has said it is fully guaranteeing both men’s lawful rights.
Kovrig also holds Hungarian citizenship.
Canada arrested Meng on Dec 1 as she was changing planes in the city of Vancouver, at the request of the United States, which has filed sweeping charges against Huawei and Meng that paint the company as a national security threat.
Meng has been charged with bank and wire fraud to violate US sanctions against Iran.
She is free on bail and denies the charges against her.