The pair are part of a 32-man squad whose opening game is away in France on Saturday, February 7.
Meanwhile the Exiles have announced that All blacks prop Ben Franks will join the club on a three-year deal.
The front row has made 42 international appearances for New Zealand and currently plays his club rugby for the Hurricans franchise in the Super 15.
London Irish have also announced that former captain Bob Casey will join the club's board after being named as the new operations director at the Exiles.
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