Poland's Prime Minister Donald Tusk on Wednesday will provide full information about the first stage of the investigation into a recent crash that killed Polish President Lech Kaczynski, government press secretary Pawel Gras said on Sunday.

Kaczynski, his wife, and an official delegation of senior officials died when the plane taking them to a ceremony to pay tribute to some 20,000 Polish officers murdered by Soviet secret police crashed near west Russia's Smolensk on April 10. There were 96 people aboard the plane, including 8 crewmembers. No one survived in the crash.

Gras said the first stage of the investigation was over, after which Polish experts would go to Moscow to continue work with their Russian colleagues.

Russian air traffic controllers earlier said the crew "did not listen" to recommendations to divert to another airport and tried to land without permission.

Poland's chief prosecutor Andrzej Seremet said earlier that Polish prosecutors would postpone revealing the black box contents until they obtain other necessary information from Russia. The final decision on whether to disclose flight details is expected in two weeks.

Russian investigators, experts and Polish specialists are jointly investigating the causes of the deadly crash. Polish military prosecutors, however, have opened their own investigation into the accident.

WARSAW, April 25 (RIA Novosti)