If U.S. President Donald Trump does not have any problematic ties to Russia, former FBI director Robert Mueller will be his best friend says Canada鈥檚 former spy chief.

Richard Fadden, who directed the Canadian Security Intelligence Service for five years ending in 2013, is confident his one-time U.S. counterpart will be the man to clear Trump of any wrongdoing in the presidential race, or prove otherwise, in what has so far been a war of words between the administration and its detractors.

鈥淚t seems to me he should want this inquiry to come about because if he is telling the truth, Muller will clear him. I don鈥檛 think that is necessarily the case,鈥� Fadden said in an interview with Evan Solomon, host of CTV's Question Period.

Mueller was named special counsel on Wednesday for the investigation into Russian cyber-attacks against the Democratic Party, as well as a probe of the Trump campaign鈥檚 alleged ties to the Russian government.

The latest salvo in the ongoing crush of controversies facing the administration comes in the form of a document described to the New York Times by a U.S. official, allegedly quoting Trump on May 10 as saying, 鈥淚 just fired the head of the FBI. He was crazy, a real nut job,鈥� and 鈥淚 faced great pressure because of Russia. That鈥檚 taken off.鈥�

Fadden says Mueller is well equipped to untangle any dealings between Trump, his team, and Russia, noting that there is a 鈥渇airly decent chance鈥� taped conversations between Trump and Comey exist, and will be entered into evidence as the investigation continues.

鈥淚 would suspect the special counsel will ask for those tapes as one of his first activities,鈥� he said.

Trump appeared to suggest on Twitter that he may have audio of conversations between himself and Comey, warning the former FBI director against 鈥渓eaking to the press鈥� after he was sacked.

Fadden also noted senior officials like Comey typically write memos immediately after high-stakes meetings, but generally do not make recordings of their bosses. He expects a detailed paper trail from Comey will serve as a valuable body of evidence as the inquiry progresses, if no recordings from Trump can be obtained.

鈥淚f it is an important issue, you go to your office, you close your door, and you write a memo for the record,鈥� he said. 鈥淚 suspect what he (Comey) wrote is probably true.鈥�

Trump鈥檚 troubles at home come as the White House increasingly seeks to turn focus to its international agenda. Last week, newly confirmed U.S. trade representative Robert Lighthizer triggered a 90-day timeline to give lawmakers notice of the administration鈥檚 intentions to renegotiate NAFTA.

Fadden says the 鈥済ridlock鈥� created by the Russia-Trump investigation could spell trouble for Canada if the president elects to move hastily on less exciting cross-border issues, such as softwood lumber and dairy tariffs, in order to make up for lost time.

鈥淚 think the real risk for Canada is on the vast number of files with which we have to deal with the U.S., said Fadden. 鈥淭here will be no one to talk to.鈥�