* Wealth fund deputy head Zarti added to blacklist
* Zarti calls reports he is rich "a joke"
* Friend of Gaddafi's son, holds Austrian passport (Adds Zarti comments)
VIENNA, March 4 (Reuters) - Austria widened an asset freeze list on Friday to include a top Libyan Investment Authority (LIA) official suspected of links to Muammar Gaddafi's inner circle, a move the man dismissed as a joke.
The Austrian central bank measures against LIA deputy chief Mustafa Zarti, who has an Austrian passport, follow international sanctions on Gaddafi's family and associates.
In a decree it described Zarti as a "close confidant of the regime in Libya" and said he was also a top executive of Libya's National Oil Corp, head of the Tamoil oil and petrol station group, and deputy chairman of First Energy Bank in Bahrain.
The LIA is Libya's main sovereign wealth fund, controlling about $65 billion of oil revenues.
Zarti told the Austria Press Agency (APA) he was not the Gaddafi clan's money man sent to Austria to spirit away billions, as local media have made him out to be.
"There is nothing behind this story, absolutely nothing," he was quoted as saying, dismissing media reports the Gaddafis and their close allies may have stashed $30 billion in Austria.
"Do I have a fortune? That is a joke," Zarti said, adding all he had was a bank account from the time he lived in Austria starting as a teenager.
He insisted the Gaddafi family had no ties to the LIA and that he had resigned from his LIA post.
The LIA worked to enhance Libya's credibility on the international stage by acquiring stakes in European blue-chip firms including Italian bank UniCredit (CRDI.MI) and British publisher Pearson (PSON.L), owner of the Financial Times.
Zarti said the LIA had a small stake in Austrian brickmaker Wienerberger (WBSV.VI) "because we believe in this company".
The 40-year-old businessman said he was on holiday in Austria to visit his family. "I always like to come to Vienna, a city I love. I was here a long time". His lawyer told APA that Zarti planned to take legal action against the Austrian state.
Austrian authorities took the opportunity to question Zarti, interior ministry spokesman Rudolf Gollia said.
"He will be questioned but there is no cause to detain him or to keep him under police surveillance," he added. Zarti's brother has also been questioned.
Austria had already frozen assets of 26 people linked to the Libyan leadership but Zarti was not on the original Austrian National Bank list published following international sanctions.
Austrian media have said Vienna is pushing the European Union to add Zarti's name to its list.
Zarti, an Austrian citizen since 2006, was close to Gaddafi's son Saif al-Islam, who studied in the capital, also home to OPEC's headquarters.
"(Saif) is a fantastic man," Zarti told APA, saying that Gaddafi's son supported democracy and human rights.
Saif, a friend of the late far-right politician Joerg Haider, lived in a luxury villa on the edge of Vienna while in the country and kept his two pet white tigers in the city's zoo.
Austria's central bank chief said this week Libyan clients had about 1.2 billion euros ($1.67 billion) in the country's banks and that authorities were trying to find out how much of this might be connected to people under sanctions.
Two of Austria's top commercial banks -- Erste Group Bank (ERST.VI) and Raiffeisen Bank International (RBIV.VI) -- say they have not found any money linked to people on the blacklist.
UniCredit unit Bank Austria said it would freeze any money it found but not comment further because of bank secrecy rules.