The signing is the latest in a string of big moves for an ambitious Israeli team stepping up the WorldTour next year after taking over the folding Katusha-Alpecin team.
The German was a free agent after terminating his Arkea-Samsic contract a year early at the start of October.
"I am looking forward for the challenge to perform on my highest level again together with team ICA, a project for the future with lots of motivated and talented riders," said the 37-year-old in a team press release.
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"I followed the team and saw its fast evolution in the last few years, and I wanted to be part of that, especially with the chance to go back and race in the WorldTour."
Griepel spent the past season at Arkea after seven years with Lotto Soudal, but hos fortune with the French team were mixed with his only win coming at Le Tropicale Amissa Bongo in January.
The team is hoping Greipel's wealth of pro experience will help them transition to the top tier during their first year as a WorldTour outfit, says team directeur sportif Kjell Carlström.
Andre Greipel sprints to win stage two of the Giro d'Italia
Image credit: Getty Images
"André Greipel has such a vast palmarès from his years in the sport up to date that we are honoured to have him join the team," said ICA directeur sportif Kjell Carlström.
"We are convinced that he can continue to win with us in 2020, but most importantly, the vast experience he brings to the team in both classics and sprinters races is going to be hugely appreciated both for the other riders as well as management."
Greipel joins Dan Martin - who signed a two-year deal in August - as the big-name signings announced by the team so far. Rory Sutherland is accompanying Martin in the move from UAE Team Emirates, while the squad will also be boosted by Hugo Hofstetter (Cofidis), James Piccoli (Elevate-KHS) and Patrick Schelling (Vorarlberg-Santic).
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