Czech Education Minister Dana Kuchtova said that political pressure over delays in receiving money from European Union funds made her decide to resign.
Kuchtova, who represents the Green Party in the current three-party Czech coalition government of Prime Minister Mirek Topolanek, made the announcement after a meeting of her party's leadership.
The European Union's top budget official Monday warned the 27-strong bloc's new members to work harder to fill out EU aid requests on time or risk a loss of billions of euros (dollars) in EU handouts.
Some, including Poland, Latvia and the Czech Republic, have failed to submit proper spending plans for the EU aid promised to them when they joined in 2004.
Topolanek on Monday urged Kuchtova to quickly act to secure the funding. Kuchtova also blamed her predecessors for the delay in receiving dozens of billions of koruna (US$ several billion).
The Greens will nominate the new minister, party chairman Martin Bursik said, but declined to give names.
The 18-member cabinet of Topolanek's Civic Democratic Party, Christian Democrats and the Greens was appointed by President Vaclav Klaus in January after months of political negotiations.
Alexey Navalny returned to Russia on January 17. He was detained upon arrival at the Sheremetyevo Airport. A court arrested Navalny for 30 days