PRAGUE (Reuters) - Czech foreign minister Josef Zieleniec, a fixture in the centre-right government since it came to power in 1992, resigned on Thursday saying he was fed up with the turmoil inside his Civic Democratic Party (ODS). But minutes after Zieleniec made his announcement at news conference, President Václav Havel issued a terse statement saying he would not accept the resignation. "I have just officially informed the chairman of (the ODS) Václav Klaus that I am resigning my function of vice-chairman...," Zieleniec told journalists. "Considering that my function of being foreign minister was directly a result of me being a vice-chairman (of ODS), it is only logical that I submitted my resignation through prime minister Klaus to the president of the republic, as stated by the constitution." Zieleniec's resignation comes just as the Czech Republic enters negotiations for its inclusion as a full member of the NATO defence alliance and prepares for 1998 talks on becoming a future member of the European Union, Havel's two key foreign policy objectives. Officials from the ministry or Prague Castle were not available to comment further on what might happen next. The news prompted the Czech crown to dip against the German mark. Zieleniec said, however, that his departure should not damage the country's foreign policy interests. "I believe that I have built up a functioning machine in this ministry that the concept of our foreign policy is very well defined, that the train is firmly on the tracks which are leading in a straight direction," he said. Zieleniec has been a frequent critic within the party of prime minister Václav Klaus's leadership style. President Havel, who is not affiliated with any political party, has rarely stepped into internal party battles. Zieleniec, aged 51, said he was upset with the way decisions were being taken in the ODS, especially with its appointment of current labour and social affairs minister Jindřich Vodička to replace the outgoing Jan Ruml as interior minister. He added that he was also upset with decisions the party had taken on its own internal financing, but he did not elaborate. "As a vice-chairman of the party and a member of its highest leadership, I was by-passed in fundamental decisions and therefore I cannot bear political responsibility for them," Zieleniec said.