This was stated by Paul Hellyer, Canada’s former Defense Minister, in a 2014 interview with RT.
Considering he was the Defense Minister from 1963-1967, it seems like he’d be a relatively authoritative and credible figure on the subject, but for a fantastic claim, I can’t find any records of such an event. Do any exist?/r/
The Canadian Defense Minister claims that all the information surrounding this are in 'secret files' which he has called upon to be released by government's around the world - so there are no **official** documents relating to it. But there are interviews of people involved in the investigation into said event - which I will go through.
In other words, he has no solid proof and for this specific event he has no proof either. I could only find one bit of information refering to UFO sightings in Europe in 1961 - The national arhives state "in 1961 the Russian newspaper Pravda reported on space saucers over Soviet territory" - whether this is related to what the former Canadian Defense Minister refered to or not is unlikely since the report also states describes "beings from Venus landing in search of cheap oriental sweets." (https://media.nationalarchives.gov.uk/index.php/cold-war-ufos/) .
In the book 'Real Aliens, Space Beings, and Creatures from Other Worlds' By Brad Steiger and Sherry Hansen Steiger, the event is described in greater detail. It follows a man called 'Bob Dean' who was a retired 'Army Command Sergeant Major', who during an interview in "the early 1990s". He stated how he became an 'intelligence analyst to Supreme Headquarters, Allied Powes, Europe (SHAPE) in Paris'. This position supposedly gave him the highest top-secret clearance in NATO.
Dean was assigned to the 'Operations Division-Supreme Headquarters Operation Centre' where he supposedly learned that it was a "war room".
In the interview, the book goes on to echo what the former Canadian Defense Minister stated - "[Dean] explained that 'SHAPE' was the Central Headquarters Command for all Allied Forces throughout Europe - from the nothern border of Norway clear down to the souther border of Turkey".
Dean supposedly became aware during his assignment of a 'secret UFO study that has begun in 1961'. This study had supposedly been triggered by an incident in 'February 1961' - which is supported by the Candian Defense Minister's claim - Furthermore, the book goes on to describe how the incident involved "thirty to fifty enormously large, circular, disc-shaped, metalic objects flying in formation over Central Europe.". This is further supported by what the Canadian Defense Minister claims - especially as in the book the movements of the craft were described as follows: "These crafts would mysteriously appear flying out of the Eastern zone, over Soviet Russia and the Warsaw Pact nations." Whilst it doesn't mention the North Pole, it does follows the rough path the former Canadian Defence Minister describes and it took place at the same time, involving the same Supreme Alliad Command system.
Supposedly this incident almost caused NATO and Soviet forces to fire on eachother but there's no evidence of this except for Dean's account.
You can read more about this specific incident and more of his accounts here:
All in all, the former Canadian Defense Minister's claims are not backed up by any official government documents but there is an account from an individual who supposedly worked in this 'SHAPE' agency. Sadly Bob Dean passed away aged 89 in 2018 though.
The account of Dean is eerily similar to that of the former Canadian defense minister's - but Dean's is much more detailed. Dean recognised he was 'violating' his 'National Security oath' by conducting this interview. He also describes a 'massive cover-up' which would fit with the former Candian Defense Minister's claim that the files are top-secret.
Here's Bob Dean's wiki: https://en.wikipedia.org/wiki/Robert_Dean_(ufologist)
You could possibly find out more about him and this specific incident there, especially as it mentions various books he's written.
He is however a well known 'ufologist' and associated with 'conspiracy theories'. So I'll leave it to you to decide whether it's believable.
^(I put a lot of effort into this so hopefully the mods don't delete it but this is probably as far as you'll get.)