The cabin of a Qatar Airways plane. AP American Airlines on Thursday said it received an unsolicited notice from Qatar Airways of its intention to make a "significant investment." 
 
 In a conversation between the CEOs of both companies, Qatar Airways said it wanted to buy about 10% of public shares, American Airlines said in a regulatory filing . 
 
 Qatar Airways filed under the Hart-Scott-Rodino Act, as required for its proposed investment of at least $808 million, American Airlines said. It added that anyone who wanted to buy over 4.75% of the company must gain board approval but that it hadn't received such a request. 
 
 "The proposed investment by Qatar Airways was not solicited by American Airlines and would in no way change the company's board composition, governance, management or strategic direction," American Airlines said. 
 
 The carrier added that it remained committed to pursuing fair competition with airlines based in Gulf nations. US airlines have raised concerns that the subsidies that Qatar Airways, Etihad Airways, and Emirates receive from their home countries create unfair competition and could squeeze them out of key markets. 
 
 Earlier in June, Saudi Arabia and other Middle Eastern neighbors cut diplomatic ties with Qatar, accusing it of supporting terrorism. The countries also closed their airspace to Qatar Airways, which could be devastating because Qatar has very little airspace relative to its size. 
 
 The airline said in April that it had seen a drop in bookings because of the US and UK governments' ban on large electronics in the cabins of certain international flights. 
 
 American Airlines shares gained about 6% in premarket trading. ||||| American Airlines is not happy with Qatar Airways' intent to invest. 
 
 American Airlines CEO Doug Parker sent a letter to employees on Thursday in response to Qatar Airways announcing their offer to acquire a 10 percent stake in the company. 
 
 In the letter, Parker uses the word "puzzling" to describe Qatar Airways' intention to invest and specifically points out "illegal subsidies" as the reason behind his criticism. 
 
 "While anyone can purchase our shares in the open market, we aren't particularly excited about Qatar's outreach, and we find it puzzling given our extremely public stance on the illegal subsidies that Qatar, Emirates and Etihad have all received over the years from their governments," Parker wrote. 
 
 Parker, a longtime critic of Gulf carriers such as Qatar, continued by saying the company is still maintaining efforts to stand against illegally subsidized companies. 
 
 "While today's news for some of our team may be puzzling, at best, and concerning, at worst, here's what we know for sure: We will not be discouraged or dissuaded from our full court press in Washington, D.C., to stand up to companies that are illegally subsidized by their governments," Parker wrote. ||||| American Airlines is no fan of the world’s favorite airline, Qatar Airways. The feeling isn’t mutual. 
 
 The gulf carrier says it is seeking a stake as large as 10% in American, the world’s largest carrier by traffic. It’s a new twist in the battle between US carriers and their Gulf rivals. US airlines have long protested that Middle Eastern counterparts Qatar, Emirates, and Etihad receive subsidies from their governments that allow them to compete unfairly. Those complaints were recently brought to the Trump administration. 
 
 In a letter to employees, American’s chief executive, Doug Parker, said that rival Qatar Airways’ plan was “puzzling given our extremely public stance on the illegal subsidies” that American alleges Qatar Airways and the other two gulf carriers receive. 
 
 Government-owned Qatar Airways has been embroiled in its own troubles, such as the US electronics ban, and a diplomatic crisis with its neighbors that allege Qatar supports terrorism, which the country denies. Its neighbors have closed their airspace to Qatari planes. 
 
 Earlier this week, Qatar Airways won the top spot from travelers in airline-analysis firm Skytrax’s world airline awards, which it dubs “the Oscars of the aviation industry.” American ranked 74th, up from 77th a year ago. 
 
 Despite its plush cabins Qatar Airways is tiny compared with American and other competitors. To compensate for its size, it is hopscotching the globe, snatching up pieces of other airlines, including British Airways’ parent IAG, Chile-based LATAM, and Italy’s Meridiana. It recently announced plans to launch an airline in fast-growing India. 
 
 Airline Qatar Airways’ stake Meridiana (pending) 49% IAG 20% LATAM 10% 
 
 American Airlines said Qatar plans to buy at least $808 million, or up to a 4.75% stake, of its stock, which would be subject to review by the US Department of Justice’s antitrust division. Qatar Airways also has designs on a stake as large as 10%, American said. That would make the airline one of American’s largest shareholders, a group that includes Warren Buffett. But the US airline hasn’t changed its stance on the subsidies dispute. 
 
 “American Airlines continues to believe that the President and his administration will stand up to foreign governments to end massive carrier subsidies that threaten the US aviation industry and that threaten American jobs,” it said in a filing. 
 
 Qatar is purchasing the shares on the open market, so there is little American Airlines can do currently. But the company’s board will have to approve any stake larger than 4.75%, and foreign voting interest is capped at 24.9%. While Qatar Airways said it only wants a passive stake in the company” a bigger position could be a tough sell. 
 
 Update: The post has been updated to include comments from the airlines.
– Shares of American Airlines stock may have jumped after news that Qatar Airways was interested in buying a 10% stake in the company, but American CEO Doug Parker threw cold water on any shareholder celebration. The announcement of interest from the airline to buy American stock worth about $808 million prompted Parker to write a letter to employees denouncing the bid, reports CNBC. "[W]e aren't particularly excited about Qatar's outreach," Parker writes, "and we find it puzzling given our extremely public stance on the illegal subsidies that Qatar, Emirates and Etihad have all received over the years from their governments," he writes, referring to two other Gulf carriers. The actual investment hasn't happened yet: Anyone trying to buy 4.75% or more of American's stock must submit a written request to the board, and that hasn't happened yet, reports Business Insider. Qatar Airways' motives were unclear, telling American only that its investment would be "passive." Quartz notes that the airline is small in comparison to US airlines and has been purchasing stakes in foreign airlines recently to beef up. In his letter Parker, attempts to allay any fear that the potential new investor could influence the airline. "Do not worry," he writes, citing a law that prohibits any foreign entity from owning 25% of a US airline. "There is no possibility that Qatar will be able to purchase enough of American to control or influence our Board, management or our strategy."