The 32-year-old attacking midfielder has been roped in by last season’s I-League runners up on a two-year contract, its media officer said.
It is not yet known when Bertos will join the squad but the club think-tank wants to play him in the CFL Premier Division beginning August 10.
Previously, East Bengal had three more World Cuppers in Majid Bishkar of Iran, Emeka Ezueogo of Nigeria and South African Macdonald Mukansi.
Bertos, who becomes their second foreigner after Ranty Martins in the upcoming season, played all the three matches for New Zealand in Group F of the FIFA World Cup 2010 — vs Slovakia (1-1), vs Italy (1-1) and vs Paraguay (0-0) — as they finished unbeaten.
Bertos began his club career with Wellington Olympic in 1997 and later played for the English clubs, Barnsley, Chester City, Rochdale and Scarborough before joining Wellington Phoenix as he has scored 35 goals at the club and youth level.
He made his debut for New Zealand in a friendly vs Iran in October 2003 and won 52 caps for his country.
He provided the assist which enabled Rory Fallon to score the winner vs Bahrain in the double legged play off match which facilitated New Zealand to qualify for the South Africa World Cup.