The presidents of Hungary, Austria, Romania and Bulgaria have urged Azerbaijan to support the proposed Nabucco West natural gas pipeline over a rival project.

Austrian President Heinz Fischer told reporters at a Central European summit in Slovakia Thursday he and his counterparts had sent a letter to Azerbaijan President Ilham Aliyev touting their preference for Nabucco West over the rival Trans-Adriatic pipeline.

A decision by the consortium controlling the Caspian Sea gas fields on which pipeline would transport the gas from Azerbaijan to Europe is expected by the end of the month.

The Nabucco proposal would pass through Hungary, Romania and Bulgaria on its way from the Turkish border to a terminus in Austria. The TAP project, meanwhile, would go through Greece and Albania before crossing under the Adriatic Sea to Italy.

Fisher, addressing reporters at the wrap-up of the Bratislava summit, said the Nabucco West option is better because it would provide more energy diversification for Central and Eastern Europe, which is all but totally dependent on Russian natural gas supplies, Croatian Radiotelevision reported.

"We believe in diversification," Fisher said. "There should be no monopoly or near-monopoly status."

The Austrian leader said the letter backing Nabucco West -- signed by himself and counterparts Traian Basescu of Romania, Janos Ader of Hungary and Rosen Plevneliev of Bulgaria -- was also supported by Turkey.

The Balkan states of Albania, Croatia, Montenegro and Bosnia, meanwhile, are backing TAP.

Basescu said Wednesday before the declaration a strong showing of support for Nabucco West was needed as the crunch time for a decision was nearing, the Romania Libera newspaper reported.

"I hope that the member states concerned -- and here I refer primarily to Bulgaria, Romania, Hungary and other countries -- will be able to sign a letter stating the Nabucco project as a priority project," he said.

"We have to have a firm and consistent stand by all member states concerned here," the Romanian president added, "and not only the states through which the Nabucco pipeline will pass, but also other beneficiary countries like Poland, for example, which can be a big beneficiary of the Nabucco gas pipeline transport."

European Union leaders are working to break the Russian grip on the regional energy sector through transit projects outlined in the so-called Southern Gas Corridor.

Most of the Russian natural gas bound for European markets runs through Soviet-era pipelines in Ukraine. Disputes between Russian energy company Gazprom and the Ukrainian government have exposed vulnerabilities in the conventional route.

Rovnag Abdullayev, director of the State Oil Co. of Azerbaijan Republic, said this month a decision between the Nabucco West and Trans-Adriatic pipelines was expected soon.

"At present, the work is under way to choose a route of transporting Azerbaijani gas to Europe," he was quoted as saying by regional news agency Trend. "The final decision will be made at the end of this month."

Both projects are expecting natural gas from the Shah Deniz II project in the Azeri waters of the Caspian Sea.