US President Donald Trump said in a radio interview Tuesday he was "very disappointed" by Russian counterpart Vladimir Putin's failure to reach a peace deal on Ukraine after their summit in Alaska.

"I'm very disappointed in President Putin, I can say that," Trump told the Scott Jennings radio show when asked if he felt betrayed by Putin's response. "We had a great relationship, I'm very disappointed." 

Trump however did not say what, if any, consequences Russia would face, despite recently setting a two-week deadline to reach a peace deal that is due to expire later this week.

The US leader added that he was not worried by a potential axis between Russia and China, despite Putin meeting Chinese President Xi Jinping in Beijing on Tuesday ahead of a massive military parade.

"I'm not concerned at all, no," Trump said. 

"We have the strongest military in the world by far and they would never use their military on us, believe me that would be the worst thing they could ever do."