Theodore Roussopoulos was one of the prime minister's closest aides
A second Greek minister has resigned after being accused of involvement in a controversial land deal that has become a scandal engulfing the government.
Minister of State Theodore Roussopoulos - who was one of PM Costas Karamanlis's closest aides - denies any wrongdoing.
His resignation comes after lawmakers voted unanimously to form a commission to investigate the land deal.
The deal saw valuable state land traded for less valuable land held by the Orthodox monastery on Mount Athos.
The exchange, with the Vatopedi monastery, is said to have cost the state some 100 million euros (£80m).
Mr Roussopoulos said he was quitting his post so he could defend himself against a "malicious and totally groundless attack".
Last month Merchant Marine Minister Georges Voulgrakis quit over the scandal, though he too insists he has done nothing illegal.
Late on Wednesday night parliament voted unanimously to set up a commission to investigate the deal.
"Comprising 23 lawmakers from all the parties, the commission... must submit its conclusions by 15 December," parliament Speaker Dimitris Sioufas said after the vote.
The Vatopedi all-male monastery is one of the largest in Greece
Mr Karamanlis' government had itself asked for an investigation over the 2007 land deal amid growing pressure both from the opposition and public.
The opposition Socialists have also called for the creation of a separate parliamentary panel, with powers to recommend criminal proceedings against ministers accused of involvement.
That motion was due to be voted on on Friday, though the Associated Press reports that the ruling New Democracy party will refuse to take part in the vote, denying it the quorum it needs to be valid.
A preliminary judicial investigation has indicated the deal was weighted in favour of the monks.
The 1,000-year-old all-male monastery, one of the largest in Greece, has denied any wrongdoing.