"Ukraine's economy in the past several months has been plummeting. Its industrial and construction sectors have also been declining sharply. Its budget deficit is mounting.

The condition of its currency system is becoming more and more deplorable ... Ukraine's economy is steadfastly heading towards a default, a halt in production and skyrocketing unemployment," Putin said in a letter addressed to 18 European leaders.

Noting that Russia and the EU member states are Ukraine's major trading partners, Putin said Moscow had agreed with the bloc in their January summit to tackle the issue of developing Ukraine's economy.

"However, all attempts on Russia's part to begin real consultations failed to produce any results," he said, adding that the EU, instead of offering Ukraine real support, only give " promises that are not backed up by any real actions."

He said since Ukraine's independence, Russia has been supporting the former Soviet Union republic's economic stability by offering natural gas at cut-rate prices.

In particular, Putin said, since 2009, the sum total of these discounts stood at 17 billion U.S. dollars, let alone another 18.4 billion dollars incurred by the Ukrainian side as a minimal take- or-pay fine.

"...Russia has been subsidizing Ukraine's economy by offering slashed natural gas prices worth 35.4 billion U.S. dollars," he added.

The president accused the EU of using Ukraine as a market to sell its highly-processed ready-made commodities, thereby creating a deficit in Ukraine's trade balance amounting to more than 10 billion dollars. That occupied almost two-thirds of the country's overall deficit in 2013.

"To a large extent, the crisis in Ukraine's economy has been precipitated by the unbalanced trade with the EU member states," Putin said. "Russia cannot and should not unilaterally bear the burden of supporting Ukraine's economy by way of providing discounts and forgiving debts, and in fact, using these subsidies to cover Ukraine's deficit in its trade with the EU member states. "

In the nearest future, he warned, Ukraine has to accumulate 11. 5 billion cubic meters of gas worth about five billion dollars to guarantee uninterrupted transit to Europe.

However, he said, there was still a discount price applied, 268. 5 dollars per 1,000 cubic meters of gas in March. "Even at that price, Ukraine did not pay a single dollar."

Putin said it was vital to hold, without delay, consultations at the level of ministers of economy, finance and energy in order to churn out concerted efforts to stabilize Ukraine's economy and ensure delivery and transit of Russian natural gas.

"However, not in a unilateral way, but on equal conditions with our European partners ... Only such an approach would be fair and balanced, and only such an approach can lead to success," he said.

Xinhuanet