McCarthy: Leaving Connacht my hardest ever call
But the 31-year-old said he was steering clear of the row which erupted between Leinster coach Joe Schmidt and Connacht chief executive Tom Sears over the move.
McCarthy, in his sixth season with Connacht in his second spell at the Sportsground, will join Leinster on a three-year deal at the end of the season and his decision led to a pre-Christmas spat between Schmidt and Sears.