Mr Klaus rejected the Irish minister's criticism of his remarks
Czech President Vaclav Klaus has become embroiled in a spat with the Irish government over the EU's Lisbon Treaty.
Mr Klaus, who is on a state visit to Ireland, angered ministers by staging a news conference with the leader of an anti-treaty pressure group.
Irish Foreign Minister Micheal Martin called the action inappropriate, only to be dubbed a hypocrite by Mr Klaus.
Irish voters rejected the treaty, which would streamline decision-making, in a referendum earlier this year.
The pact requires the approval of all 27 European Union member states, and the Irish government has come under pressure to hold another vote.
On Tuesday, Mr Klaus met Declan Ganley, the head of Libertas, a pressure group that campaigns against the treaty and was a key force behind Ireland's No vote in June.
Endorsing Mr Ganley's views at a joint news conference, the Czech president said he feared freedom and democracy would "not be enhanced" by the treaty.
The Irish foreign minister said his comments were an "inappropriate intervention in the context of such a state visit", particularly given the Irish government was in negotiations with the EU about the pact.
Mr Klaus responded by calling him a hypocrite. Mr Martin's reaction, he said, confirmed his concerns about the erosion of democracy in Europe.
The Lisbon Treaty - the set of institutional reforms aimed at streamlining the work of an enlarged EU - was drawn up to replace the draft European constitution, which was thrown out by voters in France and the Netherlands in 2005.
Ireland's rejection of the treaty has left the process at a standstill.
The Czech Republic takes over the rotating EU presidency on 1 January 2009.