South Korean and Russian diplomats will hold one-day talks this week in Seoul to discuss possible ways to revive the long-stalled six-party talks on North Korea's nuclear weapons programs, a Seoul official said Monday. Russia's deputy chief envoy to the six-party talks, Grigory Logvinov, is scheduled to arrive in Seoul for a three-day visit and hold talks with South Korea's top nuclear envoy Lim Sung-nam on Tuesday, the senior official at Seoul's foreign ministry said. "During the talks, Ambassador Logvinov and Lim plan to hold in-depth discussions about North Korea's nuclear issue and other overall matters with regard to North Korea," the official said, according to South Korean (Yonhap) news agency. They will also discuss "the current state of the Korean Peninsula after North Korea's failed rocket launch and ways to move forward on the North's nuclear issue," the official said. Diplomatic efforts to resume the six-party talks, involving the two Koreas, the US, China, Russia and Japan, were frozen in April when North Korea defiantly launched a long-range rocket. The North's failed launch ended a possible deal with the US in which Pyongyang agreed to suspend its nuclear and missile activities in return for food aid by Washington. Such conditions had been considered necessary steps to reopen the six-party talks. The six-party talks aimed at persuading North Korea to give up its nuclear ambition have been stalled since late 2008. Pyongyang has conducted two nuclear tests, in 2006 and 2009. In Seoul, the Russian envoy is also expected to discuss an ambitious plan to build a natural-gas pipeline from Russia to South Korea via North Korea, the ministry official said. The gas project, which has been discussed for about 20 years but never has materialized due in part to security tensions