"It is much cheaper and safer, of course, to construct a land pipeline, political problems put aside," he said in a Tuesday interview with the Korean Broadcasting System. "Should this [pipeline] be realized, [the overland route] would certainly be the optimal solution."
Russian natural gas company Gazprom backed away from an option to build a pipeline through the ocean in 2012, the Platts energy news service reported Tuesday. Putin, in his interview, said it was too expensive to build that type of pipeline because of the depth of the region's waters.
Putin said he wasn't trying to interfere directly in lingering tensions on the Korean Peninsula but if both sides can agree on the terms of a pipeline, it "could be carried through rather quickly."
Putin is scheduled for a state visit to Seoul later this week.
Russian energy companies are focusing some of their efforts on meeting growing Asian demands for oil and natural gas. Putin said those companies are already working in liquefied natural gas projects in the Far East to help meet Asian demands.
Wood Mackenzie, an energy consultant group, said in a September report Japan and South Korea combine to make up more than 50 percent of the global demand for LNG.