Cutting Russia's oil export duty to zero would be premature since the plan, sought by the oil industry, does not take into account a weakening rouble, Finance Minister Alexei Kudrin said on Saturday. "It is too early to talk about it," Kudrin told Vesti 24 news channel, adding that a weaker currency would boost oil firms' returns. He said the proposal also did not take into account already announced tax breaks for the industry.