This is said in the statement by the head of state posted on the White House’s website.
For the first time, “emergency situation regime” in relation to Russian Federation, which, in American administration’s view, by its actions in relation to Ukraine, endangers national security and foreign policy of the United States, was imposed by Executive Order 13660 of March 6, 2014.
As explained, 90 days before the end of the annual period President should make a decision concerning prolongation of “emergency regime” for another period. Earlier Obama gave notice to Congress on the need of such decision. Thus, regime that provides sanctions of the USA against Russia is being prolonged after March 6 for one more year.
The U.S. authorities have been imposing sanctions against Russia in three stages: except for March 6, 2014, corresponding decisions were made on March 16, March 20 and December 19.
Sanctions imposed by the USA and other western countries were applied to a number of Russian companies mainly working in energy, finance and defense industries. Also personal sanctions were imposed on Russian individuals.