Beijing, Mar 22 (IANS): China on Monday opened a trial against former Canadian diplomat Michael Kovrig, who has been held on espionage charges for over two years, less than a week after it launched proceedings against another Canadian national, Michael Spavor.

Kovrig's trial took place behind closed doors in Beijing, dpa news agency reported.

Diplomats from more than two dozen countries, including Germany, attempted in vain to gain access to the proceeding.

Kovrig and Spavor, whose trial opened on March 19, were arrested in December 2018 following the detention of Meng Wanzhou, the Chief Financial Officer of the Chinese telecom giant Huawei, in Canada at the instigation of US authorities.

Jim Nickel, the Charges d'Affaires at the Canadian Embassy in Beijing, said Kovrig had been "arbitraily detained".

"And now we see that the court process itself is not transparent. We are very troubled by this," Nickel added.

"The reason that has been given to us while we are being denied access to our citizen facing trial is that this is a so-called national security case and therefore it is a closed case, a closed court room."

At the time of his arrest, Kovrig was working as an expert for the International Crisis Group think-tank in China, while Spavor ran a cultural exchange company with North Korea in Beijing.

Both defendants face long prison terms if convicted.