"We call on the Russian Federation to immediately halt actions supporting a referendum on the territory of Crimea regarding its status, in direct violation of the Constitution of Ukraine. Any such referendum would have no legal effect," said the G7 countries in a statement.
"Given the lack of adequate preparation and the intimidating presence of Russian troops, it would also be a deeply flawed process which would have no moral force. For all these reasons, we would not recognise the outcome," said the statement issued by leaders of Canada, France, Germany, Italy, Japan, Britain, the US, along with the President of the European Council and the President of the European Commission.
"In addition to its impact on the unity, sovereignty and territorial integrity of Ukraine, the annexation of Crimea could have grave implications for the legal order that protects the unity and sovereignty of all states. Should the Russian Federation take such a step, we will take further action, individually and collectively," the statement said.
"We, the leaders of the G-7, urge Russia to join us in working together through diplomatic processes to resolve the current crisis and support progress for a sovereign independent, inclusive and united Ukraine."
"We also remind the Russian Federation of our decision to suspend participation in any activities related to preparation of a G-8 Sochi meeting until it changes course and the environment comes back to where the G-8 is able to have a meaningful discussion," leaders of the G-7 countries said.