MOSCOW, June 7. /TASS/. Russian President Vladimir Putin has called the nationalization of oil and gas sector a "complicated, dangerous process" that can lead to negative effects.

"To nationalize the whole oil industry? It is a complicated and very dangerous process that can lead to negative effects not only for the sector but for the whole economy," he said at the annual Q&A session on Thursday.

"It is not all that simple. The key thing for us is to make sure that those enterprises, whoever owns them, operate within the confines of the law, invest in production and domestic refining development, and fully fulfill their budget obligations, ensure that their enterprises are efficient and competing with peers on global markets," Putin said, adding that Russian "oil producers get it right."