That's despite the best efforts of Greenpeace, who were thwarted in their attempt to raise one yesterday.
Greenpeace did, however, the day before manage to project an image of the flag onto the castle and Prague's Charles Bridge.
Klaus has said from the get-go he won't display the 12 stars. "The castle is a symbol of Czech statehood," he said in an official statement. "There is no reason to change this historic tradition." The Czech Republic, he said, is not a province of the EU.
He was even more irked when a delegation from the European Parliament presented him with an EU flag at a meeting in December and pretty much told him he had to raise it. (Britain's "Daily Telegraph" has a fun read about that meeting.)
Some wag though has found revenge by vandalizing a huge EU flag atop one of Prague's main landmarks, a giant metronome (pictured above).
In symbolism that surely wouldn't be lost on Klaus, the metronome stands where a giant monument to Josef Stalin once stood.
-- Luke Allnutt