(ATTN: UPDATES with more details from 4th para)
WASHINGTON, June 24 (Yonhap) -- U.S. President Donald Trump said Monday he exchanged "very friendly" letters with North Korean leader Kim Jong-un.
Kim sent a letter to Trump earlier this month amid a deadlock in negotiations to dismantle the North's nuclear weapons program.
Trump responded with a letter "of excellent content," the North's state media said Sunday, raising hopes of a possible resumption of two-way talks.
"He actually sent me birthday wishes, but it was just a very friendly letter both ways," Trump told reporters at the Oval Office in the White House.
Trump, who turned 73 on June 14, revealed earlier that he had received a "beautiful" and "very warm" letter from Kim on June 10.
It was the first known correspondence between the leaders since their second summit in Vietnam in February ended without a deal.
The contents of the messages have not been disclosed, but the timing has prompted speculation that the two sides could be headed for a revival of talks on denuclearizing North Korea in exchange for sanctions relief.
Trump is set to travel to Japan and South Korea this weekend, first to attend a Group of 20 summit -- where he will sit down for talks with Chinese President Xi Jinping on the heels of the latter's state visit to Pyongyang last week -- and then to meet with South Korean President Moon Jae-in in Seoul.
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