PALO ALTO (Reuters) -Volkswagen Group said on Wednesday the technology it is developing with U.S. electric-vehicle maker Rivian Automotive ( RIVN ) could eventually be used in its internal combustion engine vehicles.

Integration of software and electronics across platforms is crucial for Volkswagen, which has struggled to unify its technology architecture across brands after repeated delays at its in house software unit, Cariad. 

The German automaker is counting on its partnership with Rivian to accelerate development of a scalable, next-generation vehicle platform and close the gap with rivals like Tesla and Chinese rivals.

"For sure, it is an extremely capable architecture and we could allow for future use to also use it for ICE, but as we already outlined our clear focus is on BEV implementation and whatever comes after that is to be decided at a later stage," Carsten Helbing, co-CEO of the joint venture RV Tech, said.

EV demand in the U.S. is expected to slow after the expiration of the $7,500 U.S. tax credit, while in Europe Volkswagen and other legacy automakers face mounting pressure from low-cost Chinese manufacturers expanding their footprint in the region.

Volkswagen agreed to invest $5.8 billion in Rivian last year, a move widely seen as an effort to strengthen its software capabilities after setbacks at Cariad.

The two companies said winter testing will begin by the end of this year, evaluating the system's performance in harsh conditions on models from Volkswagen and its subsidiaries Scout and Audi.

The German automaker's upcoming compact car model, ID.Every1, will be the first to feature the new RV Tech software and electrical architecture, with a launch planned for 2027. 

By the end of the decade, more VW Group models on the Scalable Systems Platform are expected to use the joint venture's software and electronics.