A dinner meeting Saturday between US President Donald Trump and his Chinese counterpart Xi Jinping to discuss their growing trade war went "very well", White House top economic advisor Larry Kudlow said. Kudlow's comment to journalists, as Trump and his delegation were about to take off for Washington from Buenos Aires, was the first public reaction from the high-stakes dinner lasting more than two hours. White House spokeswoman Sarah Sanders said she expected to release a statement soon. There was no immediate word from China's government. Trump and Xi, who were in the Argentinian capital over the last two days for a summit of G20 countries, had gone into the meeting in a bid to pull the world's top two economies from the brink of a full-fledged trade war. Both leaders expressed optimism as they and top aides sat down at a long hotel table adorned with flowers. "We will probably end up ending up getting something that will be good for China and the United States," Trump said. Xi stated that they shared tremendous responsibility to find a solution. "Only with cooperation between us can we serve the interest of both peace and prosperity," he said. The meeting, featuring a menu of sirloin steak, caramel rolled pancakes and Argentinian wine, went on longer than scheduled. And while it may have been tacked on to the end of two days of G20 diplomacy, it was in many ways the main event of the weekend. Trump has already imposed tariffs on more than USD 250 billion in Chinese goods - about half of the total imported into the United States each year - in an attempt to pressure Beijing to change its trade rules. Duties of 10 per cent currently on most of those goods are set to rise on January 1 to a whopping 25 per cent if a deal isn't reached. And that's not all. As Kudlow said in Washington ahead of the dinner: "If things don't work out in this US-China summit meeting, he will invoke some 267 billion dollars in additional tariffs." With US-Chinese disagreements on Trump's demands for better market access and intellectual property protections so profound, any real breakthrough was considered unlikely. But financial markets, spooked by the potential impact on the world economy, hoped that at least some kind of truce could be declared. German Chancellor Angela Merkel, also attending the G20, spoke for many when she urged progress. "We all realize that we are indirectly influenced by the fact that Sino-American economic relations are not running as smoothly as a world order needs," she said.