The pilot of the plane which crashed on Saturday, killing Polish President Lech Kaczynski, ignored several orders not to land from Russian air traffic control, a Russian military official has been quoted as saying.
Kaczynski, his wife and at least 95 others were killed when the aged Tupolev Tu-154 they were travelling in crashed in a forest while trying to land near the Russian city of Smolensk.
"At a distance of 2.5 kilometres (1.5 miles) the head of air traffic control ascertained that the crew had increased the speed of the descent," the first deputy chief of the Russian Air Force's general staff, Alexander Alyoshin, told the Interfax news agency.
"The head of the air traffic control group gave a command to the crew to put the aircraft into the horizontal position and when the crew did not implement this order, several times gave orders to divert to an alternative airport," he said.
"Despite this, the crew continued the descent. Unfortunately this ended in tragedy," he said.