Despite economic sanctions, European and U.S. businesses are continuing to operate in most sectors of Russia's economy. However, as was brought into sharp focus during the country's premier annual business summit this year, things are not going well for them.

While U.S. executives returned to the St. Petersburg International Economic Forum on Friday, after staying away under pressure from the U.S. government last year, most were looking to protect existing investments in Russia, rather than opportunities for further investment, according to a Washington Post report.

“Things are shrinking here. Business is way down, compared to last year,” Alexis Rodzianko, the president of the American Chamber of Commerce in Russia, told the paper.

Russian leaders have sent mixed signals on the country's openness toward Western investors this week. President Vladimir Putin said Friday that the country would continue economic cooperation with the West, while Natural Resources Minister Sergei Donskoi warned Western energy companies that they would be frozen out of cooperation with Moscow if they take "politically motivated decisions," an apparent reference to sanctions over the Ukraine crisis.

In addition to a lack enthusiasm for inward U.S. investment to Russia among executives at the summit, many pillars of the American business community in Russia have reportedly pulled out of the country.

“About four of five folks who were here five years ago are gone,” Bernard Sucher, a director of a Moscow-based investment bank, told the Post.

Russia's relations with its European neighbors, while somewhat better, still remain strained.

Putin said at the summit that Russia-EU trade has fallen by around 25 percent, while the value of EU exports to Russia has plunged by half.

The decision of European leaders to extend economic sanctions on Moscow, over its role in the crisis in Ukraine, until January also prompted angry response from Russian officials. Kremlin economic adviser Andrei Belousov warned that Moscow may lash back at the EU over the decision, Deutsche Welle reported.

Despite the animosity, some deals between Europe and Russia were announced Friday at the summit: State energy giant OAO Rosneft inked a pair of deals with European companies BP and Total, the Wall Street Journal reported.

However, the outlook of European businesses operating in Russia remains pessimistic. The results of a survey released this week found that optimism among European companies working in Russia is still falling, and that companies were reining in investment and growth expectations, the Moscow Times reported.