Poland is to review travel rules for its political and military elite, after the weekend plane crash in which President Lech Kaczysnki and other senior members of the establishment died.
Data on the flight recorders has revealed there were no technical problems with the plane. It also shows the crew were aware of severe weather in the area.
Responding to questions, officials in Warsaw say the pilots were not under pressure to land on time, despite the weather.
The crash happened on Saturday as the Polish government plane tried to land in thick fog at Smolensk airport in Western Russia. The party had been due at a 70th anniversary service marking the Katyn massacre, when thousands of Polish officers were shot by Stalin’s secret police.
Russia has been praised for its response to the tragedy:
“We are in sorrow, along with the Polish people. We will do our best to investigate this tragedy in an unbiased way, no stone will be left unturned.” said Russian Prime Minister, Vladimir Putin.
Moscow says officials from Warsaw will be involved in the crash investigation and were also present when the aircraft’s flight recorders were examined.
Russian President Dmitry Medvedev has been to lay flowers at the Polish Embassy in Moscow.
A day of national mourning has also been declared in Russia in the aftermath of the accident.