President Donald Trump said Friday he had made "fantastic trade deals" with China's Xi Jinping, as the pair ended a superpower summit that according to the US leader has also reaped a Chinese offer to help open the Strait of Hormuz.

Trump had arrived in Beijing seeking to seal accords in sectors including agriculture, aviation and artificial intelligence, as well as to contain differences between the two sides in a number of tense geostrategic areas -- not least the Middle East war.

Trump's overtures to Xi, whom he described as a "great leader" and "friend", were met with more muted tones by the Chinese president.

But the US leader said "a lot of good" has come out of the visit.

"We've made some fantastic trade deals, great for both countries," he said after a walk with Xi among the rosebushes in the gardens of Zhongnanhai, a central leadership compound next to Beijing's Forbidden City.

"We've settled a lot of different problems that other people wouldn't have been able to solve," Trump added, without providing details.

Xi said it was a "milestone visit", and that the two sides had to date established "a new bilateral relationship, which is a relationship of constructive strategic stability".