After a press conference of Prime Minister Sergei Stanishev, local and international media were uncertain whether an agreement would be signed or not.

Stanishev said that there had been intense negotiations and two-thirds of the contract had been agreed upon, but some decisions still had to be made.

According to Stanishev, Russia had agreed to register a joint company in Bulgaria and that Bulgaria would receive additional gas delivery to help its economy in the next couple of years. Not yet decided were questions including the distribution of shares in the new company and the ownership of the pipeline.

According to Bulgarian daily Dnevnik, Bulgarian President Georgi Purvanov and Russian president Vladimir Putin would have to work out disagreements between the two countries in the South Stream contract about the ownership of the pipeline, who would be major shareholder and transit fees for the passage of Russian gas over Bulgarian territory.

Investor.bg said that an agreement would probably not be signed. After all, "only two-third of the contract had been agreed upon," investor.bg said, quoting Stanishev.

Reuters said that Putin would seek Bulgarian assent to an ambitious scheme securing Russian expansion of gas deliveries into southern Europe when he would visit Sofia in what was possibly his last foreign visit before stepping down.

The 10-billion euro South Stream was Moscow's challenge to the rival Nabucco oil-pipeline, which would supply gas from Central Asia to the EU and diversify European supplies away from Russia, Reuters said. Failure to reach a deal on Bulgarian participation could be a major upset to Putin, according to Reuters.

Reuters said that Russia's Interfax news agency quoted an unnamed Kremlin source as suggesting Western interference was to blame for hesitation. "As soon as we achieve progress in bilateral relations, all sorts of US state department officials appear telling them 'Do you really need this?," the source was quoted as saying.

Bulgaria was torn between proving its EU credentials and maintaining its renewed ties with Russia, Reuters said. it wanted to diversify its gas sources by being partner in the Nabucco but was also attracted by the South Stream because of lucrative transit taxes.

According to Russian Interfax news agency, Putin told Bulgarian media that "Bulgaria's new allied commitments should not become a barrier to the expansion of its relations with Russia. Such an approach enjoys broad pubic support in Russia and hopefully in Bulgaria as well."