Japan's trade minister Hiroshige Seko refused any cooperation with Russia that can undermine "the unity of the Big Seven" countries, which have imposed sanctions against Moscow after the Ukraine crisis, reports Reuters.

"We will never hurt G7 solidarity over the Ukraine issue. That's a prerequisite. We are making sure each item in the current cooperation plan is not infringing on sanctions, "said Sekon. Seko announced the position of Tokyo on the eve of Vladimir Putin's visit this week.