Will Smith is literally laughing off accusations of wrongful termination and retaliation brought against him by violinist Brian King Joseph … according to new video.

Photogs caught up with the Oscar winner Monday in London, where he appeared to be working in some capacity on his new Nat Geo show “Pole to Pole With Will Smith.”

Watch the clip … when the cameraperson asks Will about the allegations brought against him by the former “America’s Got Talent” standout, Will laughs right in his face and keeps it moving.

Without even stopping to give any credibility to the question, Will hops in his waiting vehicle while the cameraperson gets buffered by security.

As we reported … Brian is suing Will for allegedly canning him after he purportedly reported a sexual harassment incident.

In the suit, Brian claims he joined Will on his “Based on a True Story” tour, but things went south during a stop in Las Vegas. Brian alleges he found evidence that an intruder had gained access to his room, along with a written note that read, “Brian, I’ll be back … just us.”

The note was supposedly signed by “Stone F” with a heart-shaped drawing. According to Brian, this made him fear he would later be targeted for unwanted sexual acts.

Brian alleged that after he reported the incident to hotel security, he was fired from Will’s tour.

But Will’s attorney, Allen B. Grodsky, told us Brian’s allegations were “false, baseless, and reckless.”