Conspiracy theorists have gone into overdrive over a rumour that the First Lady Melania Trump has been replaced a body double.

Joe Vargas took to Twitter after spotting a video of Melania standing beside her husband, Donald Trump, on the South Lawn of the White House and questioned whether she was using a body double.

In his tweet, he said: "This is not Melania. To think they would go this far & try & make us think its her on TV is mind blowing. Makes me wonder what else is a lie."

This was shared tens of thousands of times and others appeared to agree with him.

The video he shared, which was from CNN, showed the Slovenian-born model with large sunglasses on, covering much of her face.

Vargas then went on to share a side-by-side picture of Melania Trump with a screenshot of her alleged body double.

The query set off a tidal wave of tweets with many mocking the situation and using it as a means of attacking Donald Trump.

This included one tweet which read: "Okay look this "Melania body-double travels w Trump" story is silly I mean where would they find another woman willing to go places with him."

Some accused the first lady of being robotic, including Marcella Arguello who said: "It's crazy if Melania has a body double cause I thought she was a robot this whole time."

Donald and Melania Trump
US First Lady Melania Trump address US military personnel and families at Naval Air Station Sigonella as US President Donald Trump stands on stage, MANDEL NGAN/AFP/Getty Images