By Michael Hernandez

WASHINGTON (AA) – President Barack Obama has extended sanctions on Russia for what Washington says is its support of rebel groups in eastern Ukraine and continued occupation of Crimea.

Obama extended the national emergency with respect to Ukraine within a 90-day review period before its March 6 one-year anniversary, at which point it would have expired.

The original executive order that imposed sanctions targeted Russian businessmen and senior officials closely connected to Russian President Vladimir Putin, as well as a number of Russian businesses.

In line with normal sanctions regulations, they are prohibited from conducting business with Americans, and any assets they hold in the U.S. are frozen.

Washington and its European allies have imposed a series of sanctions on Russia since it annexed the Crimean Peninsula from Ukraine in March 2014, issuing separate financial penalties after it began supporting separatist rebels in eastern Ukraine.

The conflict there has continued and is languishing in stalemate. Obama said in a message to Congress that Russia’s actions “continue to pose an unusual and extraordinary threat to the national security and foreign policy of the United States,” according to the White House.

“Therefore, I have determined that it is necessary to continue the national emergency,” Obama said.

U.S. and EU sanctions have had a biting effect on the Russian economy when coupled with a staggering global decline in the price of oil, which is a bedrock industry for Russia.

The sanctions have also curtailed foreign investment with investors wary of conducting business with companies that may be blacklisted.

The EU is set to review its set of sanctions in June.

[Photo: US President Obama increased sanctiona against Russia. Photographer: Samuel Corum/AA]