General Motors and Honda have signed a non-binding memorandum of understanding that will lay the groundwork for a "North American automotive alliance," the two automakers announced via press release Thursday.

The proposed alliance would include sharing vehicle platforms and powertrains, as well as coordinated purchasing, research and development, and connected services, which would provide greater economies of scale for both companies.

While GM and Honda have discussed partnering on hydrogen fuel-cell and battery-electric powertrains before, this alliance would also extend to vehicles with internal-combustion engines, the automakers said. Planning discussions will begin immediately, with engineering work beginning in early 2021.

Honda-GM relationship timeline

Honda-GM relationship timeline

The announcement follows an agreement signed by the two companies in April to develop two new electric cars for Honda based on GM's new BEV3 architecture, and using the Detroit automaker's Ultium batteries. The two electric cars will also feature GM's OnStar telematics service, and are expected to go on sale in North America for the 2024 model year.

2006 Saturn VUE Red Line

2006 Saturn VUE Red Line

GM and Honda have a long history of collaboration. The Acura SLX and first-generation Honda Passport were badge-engineered versions of SUVs from GM-controlled Isuzu. In a later agreement, a Honda V-6 was used in the first-generation Saturn Vue crossover, while in return Honda got Isuzu diesel engines for use in Europe.

The two automakers began collaborating on hydrogen fuel-cell development in 2013, and announced a joint venture for mass production of fuel cells in 2017. Production was originally scheduled to start in 2020, but it's unclear if GM and Honda are sticking to that timeline. Only Honda currently sells a fuel-cell car, and GM has indicated it will pursue fuel cells for military and commercial vehicles.

In 2018, the automakers announced a battery partnership, with GM building batteries for both firms. Later that year, Honda announced a $2.75 billion investment in GM's Cruise autonomous-driving division, which plans to put its Origin shared autonomous vehicle into production as early as 2021.