The 32-year-old has agreed to a two-year contract with Bayonne, a French Top 14 team.
International players are not eligible to be selected for England.
Since making his debut in 2011, Tuilagi has amassed 60 caps for England, scored 20 tries, and participated in three World Cups and one Test for the British and Irish Lions.
After former captain Owen Farrell, who is leaving Saracens to join Racing 92, and Lewis Ludlam, who is moving to Toulon from the Northampton Saints, he is the most recent England player to travel to France to play club rugby.
Since making his debut in a 2011 World Cup warm-up match against Wales at the age of 20, Tuilagi has been a vital member of England’s squad.
Never better shown than in the 38-21 victory over the reigning world champions New Zealand at Twickenham in 2012, when he scored one try and was strongly involved in the other two, his powerhouse style offered the attack an extra physical dimension.
