The former WRC2 and Asia-Pacific Rally Champion has only competed in Wales three times, but he has a strong record, winning his class in a Skoda twice and finishing second on the other occasions.
Tidemand, who finished 20th and eighth overall in Monte Carlo and Sweden respectively with M-Sport earlier this year, is looking forward to his British debut in the sport’s top class and wants to demonstrate his potential to teams for 2020.
Tidemand said: “It's such a positive boost to know that I have another rally waiting, especially this close after Turkey. It’s important to have a bigger plan and I really want to show my progress and that I belong here in the World Rally Championship.
“I’m really grateful towards M-Sport and my local partners for making this happen. Wales Rally GB is an event that I like a lot – and the roads remind me of those we have back home in Sweden.
"I have great memories from Wales, but this time it will be an even bigger challenge, but I'm excited to see what I can do.”
M-Sport team principal Richard Millener added: “I think all of the manufacturers will be keen to see how he progresses over these next two events.
"We know how competitive he was in WRC2 – especially in Wales – and I’m looking forward to monitoring his progress over these next few weeks.”