WASHINGTON - Donald Trump has rejected the suggestion he has Parkinson's disease after he appeared to struggle to drink water and walk at a rally.

The US President seemed unable to lift a glass of water to his mouth at the end of a speech at West Point Military Academy in New York last weekend.

Trump, who turned 74 on Sunday, used both hands to lift the cup before tip-toeing down a ramp off the stage.

U.S. President Donald Trump has been in office since Jan. 20, 2017. Take a look at his journey, from being a successful real-estate mogul, to a reality television star, to becoming the 45th head of state of the nation.

The fragile appearance led many to speculate that he was unwell, in turn prompting Trump to tell the Wall Street Journal : "I stayed there for hours. And what do I do? I get publicity about walking down a ramp.

"And does he have Parkinson's? I don't think so".

Trump told the publication that he "ran down" the last 10 feet of the ramp and had only been struggling due to his leather-bottom shoes.

The interview was not the first time that the President has publicly addressed an incident which some are referring to as 'ramp gate'.

In a tweet sent several hours after the event he claimed: "The ramp that I descended after my West Point Commencement speech was very long & steep, had no handrail and, most importantly, was very slippery.(FA)