SEOUL: North Korean leader Kim Jong-un may opt for an unexpected route when he travels to Russia for a meeting with President Vladimir Putin, according to South Korea's National Intelligence Service (NIS).

Earlier this week, The New York Times had reported that Kim plans to travel to Vladivostok, possibly by an armoured train, later this month for talks with Putin about the possibility of supplying Russia with more weaponry for its ongoing war in Ukraine and other military cooperation.

"As it was revealed to the New York Times, there is a possibility of Kim Jong-un making a surprise move by choosing a different route than what is expected," Yonhap News Agency quoted an NIS official as saying during a parliamentary intelligence committee meeting on Thursday.

During the meeting, NIS Director Kim Kyou-hyun said the agency is closely monitoring the planned visit and sharing intelligence with other national spy agencies as a summit between the North and Russia would have a big effect on the international situation.

The New York Times report said a delegation of some 20 North Korean officials traveled to Vladivostok in late August.

"One potential stop for Mr. Kim after Vladivostok, an official said, is Vostochny Cosmodrome, a space launch centre," said the report, noting North Korea may be seeking to secure advanced technology for satellites and nuclear-powered submarines from Russia in exchange of its weapons.