U.S. Vice President Mike Pence will travel to South Korea on Sunday in what his aides said was a sign of the U.S. commitment to its ally in the face of rising tensions over North Korea's nuclear

program. Pence's Seoul stop kicks off a long-planned 10-day trip to Asia — his first as vice president — and comes amid concerns that Pyongyang could soon conduct its sixth nuclear test.

Mike Pence Getty Images

President Donald Trump has warned against further provocations, sending an aircraft carrier group to the region as a show of force. His officials have been assessing tougher economic sanctions as well as military options to curb North Korea's nuclear ambitions. Pence plans to celebrate Easter with U.S. and Korean troops on Sunday before talks on Monday with acting President Hwang Kyo-ahn. "We're going to consult with the Republic of Korea on North Korea's efforts to advance its ballistic missile and its nuclear program," a White House foreign policy adviser told reporters, previewing Pence's trip. Pence will land in Seoul the day after North Korea's biggest national day, the "Day of the Sun." The White House has contingency plans for Pence's trip should it coincide with a another North Korean nuclear test by its leader Kim Jong Un, the adviser said. "Unfortunately, it's not a new surprise for us. He continues to develop this program, he continues to launch missiles into the Sea of Japan," the adviser said. "With the regime it's not a matter of if - it's when. We are well prepared to counter that," the adviser said.

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