MOSCOW — Russian Security Council Secretary Nikolai Patrushev visited the disputed islands of Kunashiri and the Habomai group of islets off Hokkaido on Sunday, sources said.

Patrushev flew to Russian-held Kunashiri from Yuzhno-Sakhalinsk, the administrative center of the Russian Far Eastern island of Sakhalin, and while there inspected its airport, the settlement of Yuzhno-Kurilsk, called Furukamappu in Japan, and Russian border guards, they said.

Patrushev also shuttled between Kunashiri and Suisho-jima (Crystal Island) in the Habomai group by helicopter, staying on the islands for a total of five hours.

Patrushev is a former director of the Russian FSB, the successor organization of the KGB, and is a close adviser to Prime Minister Vladimir Putin, who is also a former KGB official.

Recently, Putin signed an ordinance to spend an extra 1.2 billion rubles (¥3.1 billion) to develop infrastructure in the island chain.