Russia officially joined a regional economic group in Central Asia on Monday, in the culmination of a visit by Russian President Vladimir Putin. The leaders of Kazakhstan, Kyrgyzstan, Tajikistan and Uzbekistan had approved Russia's membership in the Central Asian Cooperation Organization in May, and Putin signed a protocol Monday to formally join the group. "Russia will be a factor of stability in the region," Uzbek President Islam Karimov said. "Russia's joining the CACO was natural because it has always been close to our people and we always acknowledged its historical interests in the region." Addressing terrorism, the countries agreed to draft a common list of banned terrorist, religious and extremist groups and their leaders within three months. "In the framework of the organization, we are planning to fight the threats of extremism and terrorism, as well as work in the economic sphere," Putin said.