FEDERAL Cabinet minister Josh Frydenberg is said to be desperately seeking information on whether or not he is a Hungarian dual citizen.

The Australian reports that the Environment and Energy Minister has hired a consultant in Budapest to see if he is a Hungarian citizen by virtue of his mother.

Mr Frydenberg's mother, Erica, was born in the central European nation in 1943 and fled with her family during the Holocaust.

In a bid to account for Jews who found themselves stateless during WWII, Hungarian citizenship law states any person born in Hungary between 1941 and 1945 automatically becomes a citizen.

A child of a Hungarian citizen becomes a Hungarian citizen upon their birth.

Mr Frydenberg has not applied for Hungarian citizenship and is unsure if his mother is a citizen.

He told The Australian he did not believe he was a dual citizen.

"As someone who was born in Australia with Hungarian ancestors who arrived in Australia after the Holocaust, I would be required to initiate and undertake a lengthy and formal application and interview procedure in order to be considered a Hungarian citizen," Mr Frydenberg said. "Neither I nor anyone on my behalf has ever made such an application or ­engaged in such a procedure."

It comes as Senate President Stephen Parry resigned this week after saying he may be a British dual citizen.

Five federal MPs, including government ministers Barnaby Joyce and Fiona Nash, have been disqualified from sitting in Parliament due to their dual citizenship status.