Russian Prime Minister Dmitry Medvedev said the new sanctions on Moscow signed into law by President Donald Trump were tantamount to a "full-scale trade war," Reuters reported Aug. 3.

In a Facebook post, Medvedev said Trump's approval of the Russian sanctions bill showed his administration's "utter powerlessness."

"The hope that our relations with the new American administration would improve is finished," Medvedev said, as quoted by Reuters.

Russia's foreign ministry also said the country might impose countermeasures on the U.S., adding that "threats and attempts to exert pressure on Russia will not make it change its course or sacrifice its national interests."

Meanwhile, European Commission President Jean-Claude Juncker said the EU was also ready to retaliate within days, if the sanctions imposed by the U.S. affected European firms involved in oil and gas projects with Russia, according to a separate Reuters report.