Paralympics boss urges clarity for Tokyo after Russia doping ban.

The head of the International Paralympic Committee Tuesday called for clear guidance over the participation of Russian athletes at the Tokyo 2020 Paralympics, adding that it was "disgusting" that authorities had allegedly tampered with doping samples.

Andrew Parsons said he expected Russia to appeal MondayA's decision by the World Anti-Doping Agency to ban the country for four years from major global sports events after accusing the Russians of falsifying data from a testing laboratory.

Under the sanctions, Russian sportsmen and women will still be allowed to compete at the Olympics and Paralympics, but only as neutrals and only if they can demonstrate that they were not part of what WADA believes was a state-sponsored system of doping.

"At the end of the day, the decision will be a CAS (Court of Arbitration for Sport) decision and we will then need to react but it will be four months prior to the Games, so we will need to react quickly," said Parsons.

It will depend a lot on the decision. What we want is for the decision to be clear in the sense that there will be a clear path... on what will be the participation of Russian athletes - if any?

The IPC banned the Russian Paralympic Committee in the run-up to the Rio Games, only reinstating them this February and setting down clear criteria for their participation.

Last time, it was up to the IPC to decide on a ban but the guidelines have changed, meaning the IPC will now follow whatever recommendations WADA lays down after a potential Russian appeal.

"Of course, to know that authorities have tampered with data is disgusting and they are letting their athletes down," Parsons said.

Documents released Monday show WADA believes "deletions and alterations" to RussiaA's doping data "materially prejudiced the ability to pursue cases against 145 of the 298 athletes" with suspicious doping controls between 2011 and 2015.

The toughest sanctions imposed on Russian state authorities will also see government officials barred from attending any major events, while the country will lose the right to host, or even bid, for tournaments.

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