The United States and the European Union followed up on sanctions imposed on Russia two weeks ago, in an attempt to tackle Russian support for separatists in Ukraine, and announced a fresh round of wide-ranging sanctions, according to reports published Tuesday.

Announcing the sanctions, U.S. President Barack Obama stated that the sanctions would have a “greater impact on the Russian economy than we’ve seen so far.”

“The United States is imposing new sanctions in key sectors of the Russian economy -- energy, arms, and finance.  We’re blocking the exports of specific goods and technologies to the Russian energy sector.  We’re expanding our sanctions to more Russian banks and defense companies and we’re formally suspending credit that encourages exports to Russia and financing for economic development projects in Russia,” Obama said.

He added that the fresh embargoes imposed on Russia -- the strongest sanctions since the Cold War -- will build up pressure on Putin and the “cronies and companies” supporting Russian intervention in Ukraine.

The U.S. also imposed sanctions on United Shipbuilding Corporation -- a St. Petersburg-based defense technology company -- and five of the six state-owned banks in Russia, including the Bank of Moscow.

“Russia is once again isolating itself from the international community, setting back decades of genuine progress,” Obama said.

The EU, which reportedly does 10 times more trade with Russia than the U.S., also imposed sweeping sanctions on Russia, targeting state-owned banks by denying them access to European capital markets, imposing an arms embargo, restricting sales of sensitive technology, and the export of equipment for the country's oil industry.

The ban on export of oil technology from Europe is expected to hurt Russia the most, as it targets its two key sectors -- deep-water and Arctic drilling, and shale oil exploration.

The new measures also ban the sale of European equipment and technology that can be used for military purposes by Russia.

However, the latest U.S. and EU sanctions against Russia do not target the country’s natural gas sector or its state-owned Gazprom OAO (MCX:GAZP), as about one-third of Europe’s gas supplies come from Russia.

Earlier this week, Japan also imposed sanctions on Russia and announced that it would ban imports from Crimea and freeze assets held in Japan by individuals and groups supporting the separation of Crimea from Ukraine, Associated Press, or AP reported.

The U.S. and European economic sanctions are due to take effect later this week and will be reviewed after three months, according to the Guardian.