Poland's chief prosecutor promised today to release details of the cockpit voice recorders from the plane that crashed in western Russia last weekend killing the president and dozens of top officials.
President Lech Kaczynski, his wife, Polish military leaders and senior opposition figures were travelling to mark the 70th anniversary of the massacre of over 20,000 Polish officers by Soviet secret police in Katyn forest when the plane went down.
Russian air traffic controllers in Smolensk say they urged the pilot to divert to another airport because of thick fog, but say he ignored the advice and made four attempts to land before hitting tree-tops and crashing.
Some Polish media have speculated that Mr Kaczynski, in his determination not to miss the Katyn event, may have ordered the pilot to try to land the plane.
"No matter what the black boxes hold, it will be revealed to the public," Poland's chief prosecutor, Andrzej Seremet, told Tok FM radio today.
"The conversations, their content, will be vital in terms of proving or disproving the various hypotheses. I will not oppose revealing the contents unless they are of an intimate nature," Mr Seremet added. "The worst thing for the prosecutors to do would be to try to selectively release the information, as that could expose us to accusations of manipulating the investigation."
Russian investigators are decoding the two cockpit voice recorders recovered from the plane and have said a preliminary review could be completed by the end of this week.
The speculation that Mr Kaczynski may have ordered the pilot to land in Smolensk is based in large part on an incident in 2008, when the president flew to Georgia to show his solidarity with that country during its brief war with Russia.
The president grew irate when his pilot refused to land in the capital Tbilisi because of safety concerns, later accusing him publicly of cowardice for diverting to Azerbaijan and even pushing for him to be fired.
Belarussian leader Alexander Lukashenko, who has stormy relations with Warsaw after a crackdown on ethnic Poles, said yesterday he believed Mr Kaczynski was responsible for the crash, according to the Interfax news agency.
"The president asks whether the plane can be landed in this situation," he was quoted as saying. "But it's nevertheless the president who has the final say, it's he who decides whether the plane is to land or not, but the pilots don't have to obey."
The crash has plunged Poland into mourning and brought forward a presidential election, originally planned for October, to June.
Two days after the coffins of the first couple were brought to the presidential palace in central Warsaw for public viewing, thousands of people were still queuing for up to nine hours to pay their respects.
Biel-Flag, a Polish flag-making company, said it was struggling to cope with a surge in demand for red-and-white national flags following the tragedy."We are running out of material ... and had to hire new people to keep up with the orders, which are even more numerous than after (Polish) Pope John Paul II died," chief executive Jadwiga Gorkiewicz said, according to Polish news agency PAP.
US president Barack Obama, Russian president Dmitry Medvedev, German chancellor Angela Merkel and French president Nicolas Sarkozy are among the world leaders expected for the funeral of Mr Kaczynski and his wife on Sunday in Krakow.
Plans to bury the first couple at the Wawel Cathedral in the southern city, a place normally reserved for Poland's kings and national heroes, have sparked protests, with several hundred people gathering for a second night in Krakow yesterday to voice their displeasure.
Public support for Mr Kaczynski, a polarising nationalist and eurosceptic, had dwindled to just 20 per cent before his death and polls showed he would have lost to Bronislaw Komorowski, the candidate of Prime Minister Donald Tusk's centrist Civic Platform (PO), in the presidential vote.
Mr Komorowski became acting president following Mr Kaczynski's death and it is unclear who he will run against in an election now expected to take place on June 20th.
Right-wing Law and Justice (Pis), led by Mr Kaczynski's twin brother Jaroslaw, and the main leftist opposition party SLD, whose presidential candidate also died in the crash, are now under pressure to name new candidates to take on Mr Komorowski.