U.S. President Donald Trump spoke on the phone with Chinese President Xi Jinping on Friday and discussed the two countries' trade deal as well as North Korea.

As Pyongyang is ratcheting up rhetoric and pressuring Washington, Trump is believed to have asked for China's role in easing tensions and cooperation in implementing sanctions.

President Xi also agreed on the need to continue the dialogue momentum between North Korea and the U.S.

In a tweet, Trump said he had a very good talk with Xi concerning their giant trade deal and that they also talked about North Korea, which he said the U.S. is working with China.

But Trump did not say what was discussed. 

Meanwhile, Reuters quoted China's Xinhua news agency and reported that Xi told Trump that "all parties should meet each other halfway and maintain the momentum of easing dialogue, which serves the common interests of all parties."  

It's to be seen whether China can persuade North Korea and help ease tensions. 

The phone call comes as U.S. nuclear envoy Stephen Biegun failed to meet North Korean officials during his Asia trip.