BRUSSELS (Reuters) -- A senior U.S. envoy has said Russia must refrain from opening a naval base in Georgia's breakaway region of Abkhazia and should agree to extend the mandate of UN monitors in the region.
The NATO alliance has already expressed concern at a recent report Moscow plans a naval base in Abkhazia.
A separatist official told Reuters this week that Abkhazia expects to sign a deal over an air base and naval base within a few months, but there has been no official confirmation from Moscow.
"The possible deployment of a naval base in Abkhazia, an air base in Abkhazia and a military base in South Ossetia seems to be moving in the wrong direction," Deputy Assistant Secretary of State Matthew Bryza told Reuters in an interview.
Georgia's pro-Western leaders accuse Russia of effectively annexing Abkhazia and South Ossetia, a second breakaway region that was the focus of Russia's war with Georgia in August.
"Russia pledged to reduce its troops to the levels and locations of before the Russia-Georgia war," said Bryza, an envoy to the region. "Russia is already in violation of those commitments.... Deploying a naval base would be another violation."
He said Russia should not prevent the extension of a mandate for United Nations observers in the region, which needs extending by February 15.
"We've put compromises forward and Russia has rejected them so far," Bryza said. "We hope Russia won't reject the compromise for the United Nations."
This winter's gas dispute between Russia and Ukraine, which cut off supplies to Europe, stoked those fears further and highlighted the need for renewed investment in Ukraine, said Bryza.
The United States is considering putting its weight behind an $800 million pipeline that would de-bottleneck gas flows from Ukraine into Slovakia.
"From a U.S. perspective it makes it all the more urgent," he said. "With this less than a billion-dollar investment it is possible to increase the transit of gas by almost 15 billion cubic meters, so about half of the South Stream pipeline for a very small investment," he added, referring to Russia's preferred gas project for bypassing Ukraine.
But Ukraine will have to work hard to reassure private investors, who might view the project as too risky.
"It's time for both sides to rebuild their respective reputations...maybe this proposal to expand gas transit through Ukraine is a way to bring it all back together," Bryza said.