U.S. President Barack Obama is expressing concern about American journalists detained in North Korea and Iran.

In a statement marking the May third World Press Freedom Day, Obama said he is especially concerned about U.S. female journalists detained abroad.

It was the first time for the U.S. president to directly comment on the cases of Roxana Saberi, who is being held in Iran, and Euna Lee and Laura Ling who are detained in North Korea.

Meanwhile, Obama denounced the jailing and harassment of journalists around the globe, mentioning China, Cuba, Myanmar and Sri Lanka in particular.