U.S. President Donald Trump said the United States will add more sanctions against North Korea on Thursday, as U.S. allies have called for enforcing international sanctions as the best way to get Pyongyang to give up its nuclear weapons program.

Tensions have risen in recent weeks over North Korea's nuclear and ballistic missile tests, despite intense pressure from world powers.

"We will be putting more sanctions on North Korea," Trump said in response to a question at a meeting with Afghan president Ashraf Ghani in New York on the sidelines of the annual gathering of world leaders at the United Nations General Assembly.

A senior administration official told Reuters earlier the announcement would be sanctions-related but would not target oil.

U.S. Treasury Secretary Steven Mnuchin will hold a news briefing at 3 p.m. (1900 GMT) and U.N. ambassador Nikki Haley will brief the news media at 4:30 p.m. (2030 GMT), the White House said.

On Tuesday, Trump said in his speech to the U.N. that he would "totally destroy" North Korea if threatened and mocked its leader Kim Jong Un as a "rocket man" for his repeated ballistic missile tests.