"The Austrians must hurry up and turn the preliminary contracts into actual contracts, because time is running out and we won't wait forever," Nozari told the Austrian daily Wiener Zeitung in an interview published Friday.
Iran had "many options," he warned.
"The Islamic Republic has never signed as many new contracts as this year," he added, citing deals with countries such as India, Pakistan, Switzerland and Venezuela.
OMV is one of six shareholders in the slow-moving Nabucco gas pipeline project, aimed at bringing gas from Central Asia to Europe while bypassing Russia.
But the consortium, which also includes MOL of Hungary, Transgaz of Romania, Bulgargaz of Bulgaria, Botas of Turkey and RWE of Germany, has struggled to get construction underway in the absence of sufficient investment.
There are also fears there may not be sufficient gas supply to make the pipeline viable. A figure of 30 billion cubic meters of gas per year has been cited as the baseline figure.
Iranian Foreign Minister Manouchehr Mottaki said in January that Tehran was prepared to supply gas to Nabucco and Nozari added Friday that he was optimistic a deal could be made.
"Everybody has recognised that the Nabucco project cannot work without Iran: a country with 16 percent of the world's gas reserves cannot be ignored," he said.
"I see that the Austrians are very interested in bringing the project to a positive conclusion. Europe needs Iran and Austria, which has excellent relations with us, should set an example," he added.
The 3,300-kilometre (2,050-mile) Nabucco pipeline, on which construction is to begin in 2009 and with completion expected in 2013, will run from the Caspian Sea via Turkey and the Balkan states to Austria, in a bid to reduce the EU's energy reliance on Moscow.
