Nathan White will join Connacht at the end of the season on a three-year deal.
The tighthead prop currently plays his rugby with Leinster but he will make the switch to the West once the season draws to a close in May.
The former Waikato captain joined Leinster on a one-year deal last season after making 77 appearances for the 2011 ITM Cup finalists and in his brief time at the Blues he has earned 14 caps, including five in the Heineken Cup.
"Nathan is an exceptional scrummager and to have a player with his explosive power around the pitch opens up a huge number of opportunities for us," Connacht assistant coach Dan McFarland said.
"Nathan's a proven leader both on and off the pitch and I am looking forward to working with him here at Connacht."
Team manager Tim Allnutt added: "To have someone of Nathan's calibre and work ethic joining the squad is a huge boost to the club. Ronan Loughney has been doing a superb job at tight-head this season and Nathan's signature will add an extra layer of depth to this vital position.
"With a three-year deal Nathan has shown he believes in what we are doing here and we will use his knowledge and experience to help bring through the next crop of props through our academy structures."