"We have paid attention to this letter. I believe that scientists and former diplomats who signed it have committed at least two mistakes, since they likened those who are carrying our research and diplomatic activities in China to two Canadian citizens that Chinese competent authorities suspect of conducting activities jeopardizing the country's national security. This is brazen disrespect for those who make effort toward promotion and development of friendly exchanges between China and other countries," Hua said at a briefing.
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She went on to say that the second mistake was breaching Chinese sovereign rights and "meddling in its inner judicial affairs."
"This is overt pressure to call on the Chinese side to release two Canadians that are currently under investigation, this is disrespect for Chinese judicial sovereignty and supremacy of the law," Hua added.
She noted that as long as people did not violate the Chinese legislation, they had "nothing to worry about."
On Monday, an open letter to Xi was released, in which over 100 former diplomats and members of the academic community from around the world call on him to immediately free former envoy Michael Kovrig and businessman Michael Spavor, both detained promptly after Meng Wanzhou, the chief financial officer of Chinese high-tech giant Huawei, was arrested in Vancouver last December at the request of the US authorities on suspicions of violating Washington's anti-Iran sanctions.