Following an overwhelming bipartisan support for a bill imposing fresh sanctions on Russia, the American President, Donald Trump signed the Bill on Wednesday.The Bill also reduced the power f the president to waive or ease certain sanctions without congressional approval.
Sanctions impose on Russia for alleged Interference in 2016 elections, annexation of Crimea, military activities in Ukraine
among others.
In response, Moscow expelled about 755 American diplomats as well as seizure of American properties.This has further dampened the hope of improving Russia-America relations at least for now.
The Russia Sanctions target People and/or the following entities that:

undermine US cybersecurity on behalf of the Russia government
invest certain amounts in Russia’s energy export pipelines
conduct “significant” transactions with Russian defense and intelligence agencies (though this will come into effect six months from now)
commit, or assist in, serious human rights abuses
commit acts of “significant” corruption
provide support to the Syrian government to acquire arms
invest, or facilitate the investment of, $10 million or more in the Russian government’s privatization of any state-owned asset in a one-year period that could unfairly benefit government officials or their associates.

Read more:https://afonjaman.com/2017/08/02/facts-us-russia-sanctions/