KIEV (Reuters) - Ukrainian President Petro Poroshenko said on Friday police evidence showed that a top Kremlin aide, Vladislav Surkov, had directed "foreign sniper groups" who shot and killed protesters in Kiev a year ago.

A Russian foreign ministry spokesman dismissed the claims as "nonsense", Russia's Interfax news agency reported.

Poroshenko made his comments at a meeting with relatives of some of the 100 or so people who were shot dead over a three-day period a year ago during protests on Kiev's Independence Square (Maidan) against the Moscow-backed president, Viktor Yanukovich. Yanukovich subsequently fled to Russia.

"Just a few days ago, the head of state security told me that, in questioning, special forces operatives gave evidence that the Russian presidential aide Vladislav Surkov led the organisation of groups of foreign snipers on the Maidan," Poroshenko said, according to his website.

He also said that phone records showed there was evidence of regular conversations between Yanukovich and Russia's security services which revealed a "clear Russian link" to the shootings.

"They prepared for the shooting together in advance," he was quoted as saying.

Surkov is a senior aide of Russian President Vladimir Putin, and is often described as a 'grey eminence' in the Kremlin.

He was part of the Russian delegation in peace negotiations involving Putin, Poroshenko and the leaders of Germany and France in Minsk, Belarus, last week and was responsible for liaising with separatist leaders.

Ukrainians will commemorate the anniversary of the climax of the protests this weekend amid disillusionment at the pace of reforms and resentment that no-one yet has been put on trial for the killings.

The global police organisation Interpol has put Yanukovich on its international wanted list at the behest of Ukraine on charges of embezzlement and financial wrongdoing.

(Reporting by Natalia Zinets; Writing by Alessandra Prentice and Richard Balmforth; Editing by Crispian Balmer)