Lions chief Andy Moore says it’s the first of many quality signings his club will make before the start of the Midlands Division One season on September 4.
Wilkinson can play as a prop or hooker, but hasn’t played competitively for two years.
Moore said: “Ben will be a great addition to the squad. We have many other quality signings to unveil soon.”
Wilkinson, who has also played for Tynedale and Ampthill, added: “I’m really looking forward to starting a new challenge with an ambitious team and a great coaching staff. I can’t wait to play again after two years away!”
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Lions are due to start their pre-season programme at Broadstreet on August 21 and then they travel to Beccles on August 28.
Peterborough RUFC have a friendly at Oundle this Saturday (August 14). A scheduled friendly at Leicester Forest last weekend was cancelled because of Covid in the Forest camp.