Russia's hope for a new start to relations with the US appears over for now. Tuesday's decision by the US Congress to pass new sanctions has Russia responding with a mix of disillusionment, disbelief and possible retaliation.

They would be America's toughest sanctions against Russia since the Ukraine conflict broke out in 2014. Congress is hoping to hold Russia accountable for its alleged hacking efforts during the 2016 presidential election. Moscow denies any role. The sanctions target primarily the energy sector, crucial for the Russian economy. The Senate needs to pass the sanction legislation before it goes to President Donald Trump to be signed into law.

Read more: From Russia to Syria: Do EU sanctions really work?

End of diplomatic niceties

Upon meeting Trump during the G20 summit in Hamburg earlier this month, President Vladimir Putin expressed his hope for a "restoration of cooperation ... at least partially." Putin's press secretary, Dmitry Peskov, would not specifically comment if the new round of sanctions dashes Putin's hopes, though he said Congress' decision was "very sad." Further reaction would depend on whether the sanctions bill becomes law.

"We will not cast pearls before swine," said Russia's deputy foreign minister, Sergei Ryabkov. His biblical quote was meant as a warning that Russia would respond in kind to any sanctions. It is one of the boldest statements in months against the US, suggesting warmer relations between the two superpowers may be on ice for the foreseeable future.

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Writing on the blog for the radio station Echo of Moscow, Russia-US expert Michail Taratuta sees Putin in a bind: A mild reaction to the sanctions would make him appear weak, while a strong one would end his dream of a closer bond with a United States under the leadership of Donald Trump. The stronger reaction is more likely, he wrote.

Russia's options

Should the new sanctions become law, Russia could expel US diplomats in retaliation. Russia's response must be "asymmetrical" to make it "painful for the Americans," said Konstantin Kosachev, the chair of the foreign affairs committee in Russia's upper house, the Federation Council. Moscow's 2012 banning of US adoptions of Russian children could serve as a template of what may be in store.

Congress passed sanctions against Russia along with Iran and North Korea - symbolism that may have more impact than the sanctions themselves, the Russian journalist Konstantin Eggert told DW. "Russia's status as enemy has been sealed," he said, adding that for many in the US political establishment, Russia has become part of a "metaphorical 'axis of evil.'"

Tit-for-tat sanctions or an escalation in the Syrian or Ukraine conflicts are also possible, Eggert said.

Moscow and Brussels eye to eye?

Russian state media presented the US sanctions as a problem for Europe, given the ties Russia's energy sector has with foreign companies. The Nord Stream 2 offshore pipeline project, which will carry gas from Russia to Germany, was specifically mentioned. Germany and Austria have criticized the potential consequences of the sanctions. Brussels is wary.

The sanctions are a "threat to Europe's energy security," said Russian Minister for Economic Development Maxim Oreshkin. Others in Russia have denounced the new sanctions as a means of keeping Russian competition out of the European energy market. In response, said Kosachev, Moscow and Brussels should engage in closer discussions about a strategic alliance.