Seattle - Boeing starts a close collaboration with Embraer to counteract the pact that Airbus sealed last week with Bombardier. As a result, both Airbus and Boeing are now involved in the battle for grabbing the regional jetliner market of 100 to 160-seater.

Airbus officially took over the sales activities of the CSeries from Bombardier last week. The Canadian manufacturer couldn't manage to turn the CS100 and the CS300 into a sales success, although the existing users praise the economic and silent device for its performance that exceeds expectations.

The inclusion of the CSeries in the portfolio gives Airbus the opportunity to win new customers at the bottom of the market, where the European aircraft manufacturer does not exist with its own models.

But Boeing does not want to leave the market to its biggest rival. The American manufacturer signed a letter of intent with the Brazilian Embraer - Bombardier's biggest competitor - on July 5 to form a joint venture. The details have not yet to be revealed, but it is expected that Boeing will take care of the sales of Embraer aircraft.

Embraer took a big step this year by delivering the first new E2 jet to the Norwegian Widerøe. Embraer's E2 series are direct competitors to the CSeries of Bombardier.

Boeing will own the 80 percent of the proposed joint venture. The initial goal of the American aerospace giant was to acquire Embraer, but the Brazilian government blocked that deal with its so-called "golden share."

Boeing expects the joint venture to be formed between 2019 and 2021. The deal applies not only to passenger planes but also to military aircraft such as the new KC-390, which does not yet sell very well.