WASHINGTON: The United States would not be surprised if North Korea conducts another nuclear test, following the regime's launch of an intercontinental ballistic missile this past week, a senior White House official said Sunday, reports AFP.

"I have been concerned for some time that North Korea would conduct what would be its seventh nuclear test going back multiple administrations. And I remain concerned about that," National Security Advisor Jake Sullivan told CBS talk show "Face the Nation" in an interview.

"But it would not come as a surprise if North Korea moved forward with another nuclear test with respect to its intercontinental ballistic missile capability."

Sullivan stressed that Pyongyang had begun testing its nuclear capacity several years ago and "they have continued to test it."

North Korea said Thursday it successfully test-fired the reclusive country's newest ICBM, with leader Kim Jong Un personally overseeing the launch.

Meanwhile, North Korean leader Kim Jong Un's powerful sister dismissed the idea of talks with the United States as "a daydream" on Monday, the eve of the first US-South Korean meeting on nuclear deterrence.

North Korea fired its most powerful ballistic missile yet last week, the solid-fuel Hwasong 18 intercontinental ballistic missile, the latest of a string of launches this year.