The world’s leading economies have rejected Russian demands to pay for imported natural gas in roubles, German Economy Minister Robert Habeck said on Monday. Speaking after an online meeting with the G7 energy ministers, which he chaired, Habeck said the ministers had agreed that the demands for payment in roubles were “a unilateral and clear breach of existing contracts.” Contracts that had been concluded still applied, he said. “This means that payment in roubles is not acceptable,” he said. Russian President Vladimir Putin said last week that “unfriendly states” would have to pay for natura…