Updated

Russia coach Dick Advocaat and the country's soccer chief laid a wreath in Warsaw on Sunday to commemorate the victims of a 2010 plane crash in an attempt to defuse tensions before Russia's Euro 2012 game with Poland next week.

The complicated relationship between the two neighbours because of history, energy and security disputes, has been strained further following the air disaster near Smolensk in western Russia that killed Poland President Lech Kaczynski.

Advocaat, president of the Russian Football Association (RFS) Sergei Fursenko and Russia's ambassador to Warsaw made the short walk from their hotel to the Presidential Palace to lay the wreath, while a group of mostly elderly protesters bearing pictures of Kaczynski prayed nearby.

"We wanted to commemorate those who were killed. It was also a huge tragedy for Russia when it happened," said Fursenko.

"As soon as we came we thought of laying a wreath to honour the people who died."

Around 30 police officers stood in line to guard the Russian group. One protester's banner read, "Murders of the Polish nation" and "Katyn continues", referring to the killing of the Polish intelligentsia by Soviet secret police in 1940.

Tension over the plane crash has overshadowed a cautious rapprochement between the two countries and a planned march by Russian fans through Warsaw could be a flashpoint with locals ahead of Tuesday's game at the National stadium.

"We appreciate the gesture today, and we have nothing against the Russian nation. But the Russian government is not telling us the full truth about the crash," said 46-year-old office worker Mariola Gac.

The head of Russia's fan group told Warsaw authorities on Saturday there would be no political aspect to the march, and fans would not bear any insignia banned by UEFA.

But Poles remain concerned.

"I don't want to see Russians marching with Soviet emblems, trying to show their superiority over us. These symbols are satanic and remind of all the murders by Lenin and Stalin, of Poles and also Russians," said Gac.

Russian fans displayed illicit banners and threw fireworks during the team's opening match against the Czech Republic in Wroclaw on Friday and UEFA has launched disciplinary proceedings against the Russian FA (RFS).

"(The Wroclaw incident) is a UEFA matter. This is a standard procedure when something like this happens," Fursenko said.

"We have held a meeting and we agreed on measures to prevent anything like this from happening again. I don't expect this to occur again."

CRASH CONTROVERSY

A movement led by Jaroslaw Kaczynski, the ex-president's twin and leader of Poland's main opposition party, questions whether the crash was an accident and say Moscow may be at least partially to blame.

The group is due to demonstrate at the Palace on Sunday, as it does on the 10th of every month.

Kaczynski, known for his deep distrust of the Kremlin, and his supporters say Moscow has also not done enough to assist in the investigation.

Poles accuse Moscow of not showing good will in returning the wreckage, which still sits at Smolensk airport.

The chief of Poland's armed forces, the head of its navy, its central bank governor and lawmakers were among those killed as the plane was attempting to land in thick fog in Smolensk.

(Editing by Justin Palmer)