BERLIN (AP) — Germany's Foreign Office on Sunday expressed irritation over a ban on Christmas celebrations and songs at a German high school in Turkey.

The Foreign Office said it "didn't understand the surprising decision by the school's administration," the German news agency dpa reported.

Turkish administrators of the Istanbul Lisesi, a German high school that was established more than 100 years ago, announced earlier this week that Christmas traditions and the singing of carols would no longer be part of the curriculum, dpa reported. The news agency also reported that the school's choir had to cancel its appearance at the German Consulate's traditional Christmas concert in Istanbul.

Germany's Foreign Office called the decision "regrettable" and said it would seek dialogue with its Turkish partners over the incident.

The school itself denied on its website Sunday night that it had passed a Christmas ban, dpa reported.

About 35 German teachers work at the Istanbul school, which is subsidized with millions of euros (dollars) from Germany. The majority of the students are Turkish.