Australia lock Rob Simmons will join London Irish when he completes the Super Rugby season with NSW Waratahs.
The 31-year-old, who has played at three World Cups, has also previously played for Queensland Reds.
“Coming over to England is a brilliant opportunity for me and I can’t wait to get going,” Simmons said.
Super Rugby AU is set to continue until mid-September and Simmons is currently joint-second for most line-outs won after four rounds.
Simmons will join up with fellow Australia internationals Nick Phipps, Curtis Rona, Sekope Kepu and Adam Coleman at Irish.
The Exiles have also confirmed South African lock Ruan Botha will not be returning after a short-term loan deal earlier this season.
Botha, 28, had previously agreed to make a full-time move this summer but will now stay in Japan with Top League side Kubota Spears.