North Korean leader Kim Jong Un appears to have departed for Russia for a summit with President Vladimir Putin, South Korean broadcaster YTN reported on Monday, citing an unnamed senior government source.

Kim appears to be headed to North Korea’s northeastern border on a special train, with the summit likely to be held as early as on Tuesday, according to the report. The broadcaster earlier said the meeting could take place on Wednesday.

Earlier in the day, Russian news agency Interfax reported Kim was expected to visit the Far East “in the coming days”.

South Korea’s foreign and unification ministries, when reached by telephone, said they had no information to provide. Officials at the National Intelligence Service could not be reached for comment.

The trip, if confirmed, would be Kim’s first visit abroad in more than four years and the first since the COVID-19 pandemic.

His last trip abroad in 2019 was also to Vladivostok for his first summit with Putin after the collapse of North Korea’s nuclear disarmament talks with former U.S. President Donald Trump.