Tax implications of working for a U.S. company in U.K.

Hi. I'm just starting out freelancing and have been offered an opportunity working for a U.S. company. I am a U.K. resident and would be working remotely in U.K. as a sole trader but paid in U.S. dollars from a U.S. company. I know I would continue to pay tax in the U.K. but does anyone know if this would mean I would have to also file a U.S. tax return as well as a U.K. one and is it an easy process? If anyone has experience of this I would really appreciate any advice. Thanks.