Top Polish officials present in the cockpit of the plane of president Lech Kaczynski that crashed in Russia put pressure on the crew who ignored advice to land at a different airport, investigators said on Wednesday, AFP reports.

Kaczynski died with 95 others when his presidential jet crashed on April 10, 2010, as it attempted to land in fog near the city of Smolensk in northwestern Russia.

Tatyana Anodina, head of the Moscow-based aviation commission investigating the tragedy, confirmed that top Polish officials had been in the cockpit of the Tu-154 plane but also revealed they had pressured the crew.

"The presence in the cockpit of high-ranking officials -- Poland's air force chief and head of protocol -- and an expected negative reaction from the main passenger put psychological pressure on crew members and affected decision making regarding the continuation of landing under any conditions," she said.

She did not identify the "main passenger" but it appears she was referring to Kaczynski.

In course of the flight, the crew "repeatedly received information about the absence of adequate weather conditions" from the Severny airport in Smolesnk and a crew of a Yak-40 plane plane that had landed there earlier, she added.

"Despite this, the Tu-154 crew did not make a decision to land at a substitute airport. This fact can be considered the start of a critical situation during the flight," she said.