"If we don't have our rights respected, then as a final consequence, yes," Karl-Heinz Strauss told the Kurier paper when asked if the company was ready to withdraw from Hungary.

Porr has blamed missed payments primarily from Hungary but also from Romania for a 90 million euro ($121 million) write-down on projects in eastern Europe that could push it to a loss of up to 80 million euros this year.

Strauss said the M6 motorway that Porr built with a partner in Hungary has been ready for a year but it has still not been paid. "They are complaining about problems that have not been there for a long time," he said in an interview printed on Saturday.

He played down the overall impact of state austerity measures on Porr's business. "It will continue to go well next year in Austria, Germany, Poland, Romania and Bulgaria. We expect less business in Slovakia, Hungary, Croatia and Slovenia. Basically I am not pessimistic. There is a lot of project tenders."