There could be a sinister reason behind why Vladimir Putin walked with one arm by his side when he met Donald Trump last week.

The Russian leader was in Alaska to attend a peace talks summit with the US President, though discussions failed to provide any concrete results.

Footage of the pair walking together shows Putin with his left arm swinging in time with his steps, while his right arm is mostly kept down by his side and is static.

Putin's bizarre step has been observed on numerous occasions, with many trying to solve the mystery and find out why he walks in this way.

After analysing footage from throughout the years, a team of experts believe they've cracked the code.

Researchers believe Putin's strange steps could be a trait linked to weapons training he received during his time with the Soviet KGB.

Analysts from Portugal, Italy, and the Netherlands wrote: 'According to this manual, KGB operatives were instructed to keep their weapon in their right hand close to their chest and to move forward with one side, usually the left, presumably allowing subjects to draw the gun as quickly as possible when confronted with a foe.' 

Studying various other Russian figures they found that many of them walked with the 'gunslinger's gait', particularly if they'd had KGB training in the past.

Putin worked for the KGB for 16 years before retiring to pursue a career into politics. 

It comes after Kremlin footage captured the Russian leader’s knee jolting repeatedly as he stood alongside his US counterpart at the end of their brief exchange following a joint press conference at the summit in Alaska.

The pair, flanked by security teams and aides, spoke for a short time, with a translator stepping in to assist their conversation. 

Video clips shared online showed the Russian leader repeatedly dipping one knee as he stood beside the 6ft 3in former president at Elmendorf-Richardson air base in Anchorage - before departing without agreeing to a ceasefire in Ukraine.

But the unusual movements was seized by eagle-eyed Ukrainians, who ridiculed the 72-year-old’s fidgeting and speculated about the state of his health.

They even claimed he wore a 'light exoskeleton' as well as thick-platform shoes to overcome his 'Napoleon complex' and minimise his height difference with the US president.

An exoskeleton is a wearable robotic device designed to assist or augment the posture of the person wearing it.

Observers also noted the striking difference in stature, with Trump’s 6ft 3in frame towering over the 5ft 7in Russian leader despite Putin’s visibly elevated footwear.