Russia's parliamentary polls won by the ruling party and which sparked mass protests were marred by 3,000 violations, prosecutors said Wednesday, but they did not back allegations of mass rigging.

Irregularities ranged from conflicts of interest on election committees to unlawful voters, prosecutors said in a report delivered by Russia's prosecutor general Yuri Chaika to President Dmitry Medvedev.

Up to now, 95 people had faced administrative consequences for the violations, it said.

But the report made no mention of any criminal cases and stopped well short of backing opposition claims that there was mass rigging to boost the ruling United Russia party of Vladimir Putin.

"Around 3,000 violations of electoral law have been found... Following actions by prosecutors, 95 people have been brought to administrative responsibility," said the report published on the Kremlin website.

It said that in the northern Leningrad and Pskov regions as well as the Siberian Nenetsky Autonomous Area prosecutors thwarted attempts to include in election committees people who were working for candidates.

Individuals with criminal records were also excluded, it added.

In the Siberian Altai region, the voter lists included 986 people who should not have voted as they were either deemed legally incapable of casting their ballots or they were in jail.

Officials had also recorded cases in which electoral lists had not been properly drawn up in seven regions, including the important Siberian regions of Krasnoyarsk, Novosibirsk and Omsk, the report said.

It also also noted cases across Russia of illegal campaigning -- notably on election day itself and the day before -- as well as the illegal financing of election campaigns.

Putin's party polled less than 50 per cent of the vote -- down from over 64 per cent in 2007 -- but still clung on to a majority of 238 seats in the 450-seat State Duma in the 4 December polls.

The opposition, which posted numerous videos on the Internet appearing to show ballot-stuffing, has said United Russia's results would have been far worse in fair polls.

The authorities have vehemently rejected calls from the opposition for new elections to replace the current parliament, which met for its first session at the end of last year.