WARSAW, April 19 (Xinhua) -- European Council President Donald Tusk was questioned in a prosecutor's office in Warsaw and testified as a witness in an investigation which was related to an issue during the period when he served as Polish prime minister.
The prosecutor's questioning lasted for more than nine hours and ended around 8:20 p.m.local time. At the following press conference, Tusk said he was not entitled to disclose any information regarding it. He added, however, the whole matter was "of a political character."
Tusk expressed that he will cooperate to clear up the issue. Though having immunity, he chose not to invoke it and made himself available for questioning.
"I want to show the best will possible. As long as I am convinced that the point is to clear up the issue, I will be available," he declared before questioning.
During the evening press conference, however, he added that he would use the immunity if he came to a conclusion that certain issues are purposely used against him, making it impossible for him to perform EC President's duties.
The District Prosecutor's Office in Warsaw said that "the investigation in which Mr. Donald Tusk is to be heard as a witness is the overruling of the powers by the members of the Military Counterintelligence Service (SKW) management, as a result of establishing cooperation with the foreign service without the required approval of the prime minister."
The website of SKW said that the investigation was initiated regarding in a case concerning the cooperation of SKW with the Federal Security Service of Russia (FSB).
PAP reported that SKW and FSB established cooperation on investigation of the plane crash on April 10, 2010 near the Russian city of Smolensk. Besides then Polish President Lech Kaczynski and his wife, more than 90 senior officials and plane staff died in the crash.