Boeing is reportedly in talks with US automakers to buy more of their parts business.

The company already owns more than a dozen U.K.-based parts suppliers.

A Reuters report said the deal could be worth up to $400 billion.

The deal would help Boeing boost its global business by expanding into parts manufacturing, as well as expand its automotive business, which relies on parts suppliers to make parts for vehicles.

A Boeing spokesperson said: We are actively discussing potential opportunities to work together with automotive companies to expand our business and expand our footprint in the global marketplace.

Boeing currently manufactures some 3.5 million vehicles worldwide, mostly in the U, Europe and Asia.

A number of big carmakers are exploring possible acquisitions of parts suppliers as they struggle to compete in the auto market, which is expected to be worth $4.6 trillion by 2020. 

Boechs recently announced it will stop manufacturing the 737 MAX aircraft and shut down its 737 MAX-100 air-transport plane.

Boeing said the 737 will remain in service, but that it will “temporarily halt production of the 737MAX air-to-air aircraft in order to focus on the 737 Max MAX aircraft, which will be built in our new Everett, Washington facility.”

Budget-conscious automakers have struggled to meet rising demand for their cars and trucks in a shrinking market.

In September, GM, Ford and Fiat Chrysler unveiled plans to merge their parts and engineering businesses.

Ford said it was in talks for a $600 million takeover, while Ford said that the deal would be contingent on its “performance of a series of investments.” 

GM said it would invest $10 billion to acquire its parts business and its global engineering arm.

The plan was for GM to invest $15 billion in its parts-supply chain.