It's perhaps the most famous speech President Kennedy never made.

Due to be delivered in Dallas, Texas on November 22 1963, JFK was shot twice during the presidential motorcade, dying just 30 minutes later.

He had been on a political trip to smooth over frictions in the Democratic Party.

But thanks to new technology from St Andrews University, his last speech can be heard for the first time.

The Edinburgh company behind this creation used 831 of JFK's speeches to painstakingly piece together the audio.

Chris Pidcock, chief technical officer at CereProc, the company behind the technology, said: "This project started when a few companies wanted to recreate the voice of JFK based on the speeches he'd already given.

"So what we would do is take speeches that he made, cut them up, and then stitch those together in new ways to make new words and phrases that he'd never said before."

The JFK Library Foundation were involved in the process, and gave permission for the project to go ahead.

Professor Phillips O'Brien, head of strategic studies at the University of St Andrews said: "It's great technology it's fascinating stuff to hear that speech being given.

"We'll never know exactly what the speech will be like, but the technology does provide interesting glimpses.

"I've always thought it's like putting colour in First World War photographs, and that changes our knowledge to a true way.

"They saw it in colour, we've always seen it in grays and black and whites, it gives it a completely different feel."