U.S. President Donald Trump said Sunday the United States has given up nothing ahead of his planned summit with North Korean leader Kim Jong Un, while Pyongyang has already curtailed its nuclear weapons development.The U.S. leader said on Twitter, "We haven't given up anything & they have agreed to denuclearization (so great for World), site closure, & no more testing!" But Trump acknowledged that the eventual outcome of his talks with Kim, which could occur in late May or early June, is uncertain, with Pyongyang yet to agree to dismantle its nuclear arsenal and the permanent denuclearization of the Korean peninsula."We are a long way from conclusion on North Korea, maybe things will work out, and maybe they won't - only time will tell," Trump said, "But the work I am doing now should have been done a long time ago!" Trump, as is often the case, offered his thoughts after hearing television news commentary he didn't like, this time from NBC News anchor Chuck Todd.The president said, "Sleepy Eyes Chuck Todd of Fake News NBC just stated that we have given up so much in our negotiations with North Korea, and they have given up nothing."Todd said of Kim's overtures ahead of the summit, "He seems to be giving very little but making it seem like he's giving a lot."The television newsman said, "There's not many pre-conditions the United States is asking for. So far in this potential summit, North Koreans have gotten a lot out of it. What has the United States gotten yet? We don't have a release of any of those Americans that they held captive, we don't have a pledge of denuclearization as the ultimate goal. There's a lot of things they are not promising that is raising some red flags."