VILLAROCHE, France -- France will pump hundreds of millions of euros into developing low-emission aircraft, engines and aviation fuel in the coming years, President Emmanuel Macron said Friday. Paris would dedicate 300 million euros ($330 million) to aircraft and motor research, Macron said during a visit to jet engine maker Safran just outside the capital. Public and private cash would also be funnelled to developing small electric or hydrogen-powered aircraft and renewable fuels, including a biofuel plant for southwest France. "We French have to be the champions of ultra-clean planes... and it is in our power to do it," Macron said. Aviation is a key sector of the French economy, with leading companies including Safran, Airbus and Dassault. The industry employed 691,000 people in 2020 -- seven percent of France's industrial workforce --  with annual revenues of 186 billion euros, according to national statistics authority Insee. Activity is taking off again after a Covid-enforced slump, with global passenger numbers set to match 2019's figure of 4.5 billion. Airbus, which by itself accounts for around half of global airliner sales, expects the global plane fleet to double to around 46,000 by 2042. But French and European industry faces fierce competition from the United States and China in the race for eco-friendly options. The stakes are high, with up to four percent of global greenhouse emissions coming from air transport. Macron's announcement comes before the opening next week of the Paris Air Show, a landmark on the global aerospace industry calendar. The extra cash for low-emission planes was not welcomed by all. "The zero-emission plane doesn't exist," leading French Greens MP Sandrine Rousseau told broadcaster Franceinfo before Macron spoke. "We might as well go looking for the Yeti". Instead, "we should immediately take measures like reducing the number of trips by plane," she added. France recently banned short domestic flights on routes that could be covered in less than two-and-a-half hours by high-speed rail.