Foreign Affairs circulates a "persona non grata" list in June each year, warning its embassies, consulates and other missions to bar them from local events marking Canada's birthday.
The department has refused to release its latest list, but The Canadian Press obtained last year's version — likely little changed for 2014, with the possible inclusion of Russia for the first time.
North Korea, Fiji, Belarus, Iran, Syria, Madagascar and Guinea-Bissau are prominent, largely because of Canada's disapproval of unelected or badly behaved governments.
Taiwan is also on the list, though only because Canada does not recognize the island as a state rather than from any disapproval of the government.
Sudan has special status: officials can be invited, but only those not named in arrest warrants from the International Criminal Court.
Last year's list, created before Canada's vocal diplomatic rift with Russian President Vladimir Putin over incursions in Ukraine, does not include Russia — but Russian officials are likely unwelcome at receptions this year.
Canada's relations with Myanmar have improved in recent years, and last year's list allowed civilian officials from the Asian country formally known as Burma to attend Canada Day receptions.
An accompanying memorandum from deputy minister Morris Rosenberg also notes the invitation restrictions apply for events being held in Canada as well.
"The same considerations would apply to any official Canada Day event hosted in Ottawa and involving the local diplomatic corps," he said.
The memo and related materials were obtained under the Access to Information Act, with a few parts blacked out under an exemption protecting international relations.
Asked to comment on the list the department provided to The Canadian Press, a spokesman said "it is not our practice to provide lists of country representatives invited or not invited to functions held at our missions abroad."
"I'm afraid that's all I have at this point," Ian Trites said in an email.
Trites did not respond as well to specific questions about Russia's status on this year's persona non grata list.
Canada has applied sanctions against more than five dozen Russians and others linked to the Ukraine crisis, while Russia has imposed sanctions against more than a dozen Canadians in retaliation.
One of Russia's close allies, Belarus, appears on the 2013 list with the most detailed explanation for its exclusion.
"The most recent election, held in December 2010, was marred by a lack of transparency in the vote counting process, a violent crackdown on protesters, and the detention of most of the opposition presidential candidates," says the document.
"Given the current situation in Belarus — which continues to deteriorate — Canada sees no reason to modify its policy of limited engagement."
On Friday, Foreign Affairs publicly released another list, naming the countries favoured for foreign aid from Canada. The document added Myanmar and six others to the 20 countries first identified in the 2009 version, while dropping Pakistan and Bolivia.
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