'Were Ukraine to sign up, there would be a common economic space encompassing the “Big Four” republics of the Soviet era, with a combined population of 213 million and stretching from the European Union to China. Its political, military and economic centre would be in Moscow, where Mr Putin is expected to reclaim the presidency in 2012 for up to 12 more years.

A common currency would give him an economic lever to challenge the US dollar and the euro by creating a regional reserve currency. Finance Minister Aleksei Kudrin stated last month that Russia, as the world’s largest energy supplier, may soon sell oil in roubles.'

Read more: Vladmir Putin Forging Ahead With Vision of Eurasian Empire