Conservative MPs say recent comments made by Canada鈥檚 former ambassador to China about the upcoming federal election are 鈥渧ery disturbing鈥 and should be investigated by CSIS.

John McCallum told the South Morning China Post earlier this week that he warned his contacts in China's foreign ministry that further 鈥減unishments鈥 against Canadian exports could help the Conservatives win the fall election 鈥 a win that he said wouldn鈥檛 be in China鈥檚 best interests.

Foreign Affairs Minister Chrystia Freeland called McCallum鈥檚 comments 鈥渉ighly inappropriate鈥 and said he doesn鈥檛 speak for the federal government. Conservative Leader Andrew Scheer accused McCallum of inviting foreign interference in the upcoming election.

In a letter sent to CSIS Director David Vigneault on Friday, deputy Conservative leader Lisa Raitt and public-security critic Pierre Paul-Hus said McCallum provided advice to the Chinese government on Canada鈥檚 upcoming federal election.

鈥淲e believe Mr. McCallum鈥檚 actions, as confirmed by his own public statements, deserve the utmost scrutiny of your agency,鈥 the letter reads.

The letter goes on to say the advice was partisan in nature and that McCallum encouraged China to take actions in order to influence Canada鈥檚 democratic process.

鈥淐anadians expect that the upcoming election will be conducted in a free and fair manner, and that any and all incidents of foreign interference will be fully investigated.鈥

The MPs say McCallum鈥檚 actions are inappropriate, particularly against the backdrop of the detention of two Canadians, Michael Kovrig and Michael Spavor, who have been held in China since December 2018.

McCallum was fired in January after publicly weighing in on the arrest of Huawei executive Meng Wanzhou in Vancouver.

Canada and China have been locked in a diplomatic dispute since her arrest, with ripple effects on trade. China has suspended key agricultural imports of Canadian canola, pork and beef.

Canada has not appointed a new ambassador to China since McCallum鈥檚 departure. Prime Minister Justin Trudeau was asked about the vacancy on Friday, but Trudeau sidestepped the question.

"We have excellent diplomatic representation in China who are doing an outstanding job and we are making sure we are moving forward in the right way, in a way that is going to both protect Canadians, uphold the rule of law and keep a path forward for our economy and the investments," he said.

"Getting that balance right is something that we are taking very seriously."

Since leaving the diplomatic role, McCallum has worked as a Toronto-based advisor on Canada-China business relations.