US President Donald Trump on Sunday said there had been “big progress on Russia,” without giving details. In a brief post on his social media platform, Trump wrote: “BIG PROGRESS ON RUSSIA. STAY TUNED!” The remark comes a day after his talks with Russian President Vladimir Putin in Alaska, where both leaders discussed the Ukraine conflict.Meanwhile, Trump’s special envoy Steve Witkoff said that the US President and his Russian counterpart Putin agreed to “robust security guarantees” for Ukraine during their high-stakes summit in Alaska.“We agreed to robust security guarantees that I would describe as game-changing,” Steve Witkoff said on CNN.