US President-elect Donald Trump has continued his feud with John Lewis after stating that the civil rights icon "got caught in a very bad lie" when he claimed that he had never previously boycotted a presidential inauguration.

Lewis and Trump engaged in a war of words after the Democrat announced he would be boycotting Trump's inauguration and the Republican responded by criticising Lewis' district in Georgia.

Trump's comments, particularly coming as they did over Martin Luther King Jr weekend, prompted outrage from supporters of the civil rights activist.

Now, in a pre-taped interview with Fox News which is set to air on Wednesday (18 January), Trump claimed that the Georgia congressman "got caught" lying about never having missed an inauguration.

Lewis said Trump's would be the first inauguration he had missed since being a sitting member of Congress, despite having not attended George W Bush's 2001 inauguration, a fact that he now says he forgot.

"So he got caught, and it's pretty bad. And it's making him look bad, frankly," Trump said in the Fox News interview, seen by The Hill.

"He conveniently doesn't remember. How do you forget if you go to an inauguration? I can tell you, when I was at the inauguration, you don't forget something like that," Trump added.

"This is a transition, and a very important transition ... we have to have a smooth transition, and President Obama understands that very well, and that's why he's been so gracious.

"And I think for [Lewis] to have grandstanded, because I think he just grandstanded ... and then he got caught in a very bad lie."