* IOC Executive Board to announce decision on Tuesday
* Russia has been accused of state-sponsored doping by WADA agency
* Anti-doping agencies want Russia excluded from Pyeongchang
* Russia says it is victim of political dirty tricks (Adds context)
By Brian Homewood
LAUSANNE, Dec 4 (Reuters) - Under huge pressure from all sides, the International Olympic Committee (IOC) will decide on Tuesday whether to ban Russia from next year's Winter Olympics over alleged institutionalised doping.
Anti-doping agencies and many athletes want Russia to be completely excluded from Pyeongchang, but Moscow has vehemently denied state involvement and complained of political manipulation.
Facing the same decision ahead of the Rio Summer games 18 months ago, the IOC stopped short of imposing a blanket ban and instead left decisions on individual athletes' participation to the respective sports federations.
Russia's anti-doping agency (RUSADA) has been suspended since a report by a World Anti-Doping Agency (WADA) commission headed by Canadian lawyer Richard McLaren in 2015 found evidence of state-sponsored doping in Russia and accused it of systematically violating anti-doping regulations.
A further WADA report by McLaren in 2016 found that more than 1,000 Russian competitors in more than 30 sports had been involved in a conspiracy to conceal positive drug tests over a five-year period.
In the last month, the IOC's own commission has banned more than 20 Russian athletes from the Olympics for life over doping violations at the 2014 Winter Games that Russia hosted in Sochi, while WADA has said that Russia remains "non-compliant" with its code.
The options facing the 15-member IOC Executive Board, which meets on Tuesday, include a blanket ban on Russia or allowing Russian athletes to compete in South Korea as neutrals. This would mean that they could not participate under Russia’s flag and the Russian anthem would not be played at medal ceremonies.
The IOC could also do what it did at Rio and defer the decision to the international sports federations. Although Russia was barred from athletics and weightlifting, it was able to send around 70 percent of its original 387-strong squad after other sports' federations accepted its athletes.
IOC President Thomas Bach said at the time that the decision balanced "the desire and need for collective responsibility versus the right to individual justice of every individual athlete".
The IOC could argue that the fundamental situation has not changed since then despite the evidence produced from the Sochi games and the publication of the second part of the McLaren report.
"The IOC has a delicate decision to make," sports marketing expert Patrick Nally said.
"On the one hand, it needs to show WADA and the world's media that it is chastising Russia, but at the same time it needs to be temperate in its approach ... Banning them outright will, I think, be too negative a step.
"A compromise is necessary if the IOC wants to maintain stability. It can withstand media criticism but it can't withstand an all-out war with one of its influential members."
Last week, Joseph de Pencier, head of the iNADO umbrella group of national anti-doping agencies, said allowing Russia to take part in Pyeongchang would raise doubts about sport's willingness to root out drug cheats.
Russian officials have said their country is the victim of a politicised dirty tricks campaign designed to besmirch its reputation and curb its sporting success.
On Monday, two Russian Olympic medallists urged the IOC to allow Russian athletes to compete.
"I passionately believe that it is not the answer to ban innocent, clean, young Russian athletes from competing under the Russian flag in Pyeongchang," said Svetlana Zhurova, who won Olympic gold in speed skating in 2006.
Evgeni Plushenko, a four-time Olympic figure skating medallist, said making Russians compete as neutrals would be "unfair on them and all their competitors who in some way would feel that the competition and Olympic spirit would have been devalued". (Writing by Brian Homewood; Editing by Richard Balmforth and Kevin Liffey)