Bulgaria was strongly represented at a recent regional summit in Istanbul, where Vladimir Putin, the Russian president, won backing for a €10bn project to build a second natural gas pipeline beneath the Black Sea.

Both Georgi Parvanov (left), president, and Sergey Stanishev, prime minister, enthused over South Stream, a joint venture between Gazprom and Eni, the Italian energy group.

The 900km pipeline would carry Russian gas to Bulgaria’s Black Sea port of Burgas before continuing across Greece and beneath the Adriatic to Italy. Gazprom and Eni already operate a shorter pipeline between Russia and Turkey.

Mr Parvanov, re-elected last year by an overwhelming margin in a popular vote, has become Sofia’s chief negotiator with Moscow, say Bulgarian analysts. This follows the sacking last June of Rumen Ovcharov, the powerful energy minister, who is being investigated for alleged corruption.

The 50-year-old president’s new role deepens his influence over domestic politics, although he has been overtaken as Bulgaria’s most popular politician by Boyko Borissov, the high-profile mayor of Sofia, according to opinion polls.

At an interview held in a formal ante-room to the presidential office, Mr Parvanov takes sips of mineral water between carefully phrased answers. A historian by profession, he is keen to stress that the era of Russian political patronage is over.

“We’re attempting to build modern relations [with Russia] which are firmly on an economic basis,” he says. “We can afford to have US military bases on our territory, as well as energy projects with Russia, because we believe both are part of our national interest.”

If realised, South Stream would strengthen a long-standing partnership between Gazprom and Bulgargaz, the state-owned gas group that already operates pipelines carrying Russian gas to Turkey and Greece and takes off a small quantity for domestic use.

Bulgaria, a Nato member since 2004, lobbied hard for a permanent US presence after making facilities available during the invasion of Iraq. Last year, the Socialist-led government signed an agreement for US troops to use three military bases for training and rapid deployment to the Middle East.

Energy policy, too, is about keeping a balance, Mr Parvanov says. “We have contacts with Moscow because Russia is a major source of energy for the region. But our vision is to be a part of European Union energy policy, and we’re trying to diversify our oil and gas sources as well as the pipeline routes. In this context we work with one or more EU partners.”

The government has already signed up to the Nabucco project, led by Austria’s OMV group. It aims to diversify the EU’s energy sources by transporting gas to central Europe from the Middle East and central Asia through Turkey, Bulgaria and Romania.

Bulgaria shares a 49 per cent stake with Greece in another pipeline project to carry Russian and Caspian oil from Burgas to the Aegean port of Alexandroupolis, bypassing the congested Bosphorus. Russia, which holds 51 per cent, would control the project.

A former Socialist party leader, the president maintains ties with senior party members who have made the transition from the communist nomenklatura to wealthy pro-European businessmen.

At times he appears to overshadow his prime minister, the 41-year-old Mr Stanishev, who has the difficult task of managing an unwieldy grand coalition set up to ensure Bulgaria would join the European Union on schedule.

While the president lacks executive powers under Bulgaria’s constitution, he personally appoints members of supervisory bodies as diverse as the supreme judicial council and the media regulator.

One trusted adviser, Boris Velchev, took over last year as prosecutor-general with a brief to improve the performance of public prosecutors, in order to secure convictions of corrupt politicians and organised crime bosses.

Mr Parvanov accepts that not enough has been achieved: “The prosecutor-general is pro-active, steps have been undertaken to prevent the corrupt practices, laws on the judiciary have been amended. But so far I haven’t seen radical changes on the ground.”

He shows no embarrassment at being asked about recent press reports of his involvement in a project run by the communist-era intelligence service. A dozen presidential advisers have also been named in local media as having past secret service connections.

“What we’re talking about is my role in editing a historical book which was requested of me by a member of the foreign ministry. As in many other cases, it turns out that this person was working for the intelligence services at the time,“ Mr Parvanov says.

Bulgaria is the last country in eastern Europe to open secret files kept on its citizens. After previous governments refused to make a move, a special parliamentary commission was set up this year to examine the files of 140 politicians who are believed to have collaborated with the intelligence service under communism.

Mr Parvanov has opted for transparency by posting the contents of his secret file on the presidential website. “Thank God everything is in the public domain and now we can put it behind us,” he says.

Copyright The Financial Times Limited 2018. All rights reserved.

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