Brazilian aircraft maker Embraer on Tuesday announced the sale of 40 E-175 jets to US carrier SkyWest.

SkyWest will operate the aircraft under a Capacity Purchase Agreement (CPA) with United Airlines.

According to Embraer, before the sale of 40 E-175 jets, the company has made contracts with United Airlines for 30 E-175 jets last month.

In addition to the 40 jets bought, SkyWest may take another 60 firm orders for the E-175 jet, if it is awarded other CPA contracts with major US airline partners.

"The agreement also includes options for another 100 E-175s, taking the total order potential up to 200 airplanes," Embraer said in a statement, adding that if all 100 firm orders get the green light, the order's total value will reach 4.1 billion US dollars.