MOSCOW (AFP) - Russia's lower house of parliament on Tuesday refused to hold a minute's silence for murdered opposition activist Boris Nemtsov, with only two lawmakers standing in a show of respect.

Opposition lawmaker Dmitry Gudkov proposed that the lower house of the Duma hold a minute's silence at its first full session since the brazen assassination of one of President Vladimir Putin's most outspoken critics sent shockwaves around the world.

The 55-year-old former deputy prime minister, who was gunned down on a bridge opposite the Kremlin on Feb 27, was himself a lawmaker from 1999 to 2003.

"Despite the fact that not everyone shared his political views, I think it would be the right thing to do on a human level to honour his memory with a minute of silence," Gudkov said.

But nationalist politician Vladimir Zhirinovsky objected: "Someone dies every week. Should the Duma stand up every time?"

Speaker Sergei Naryshkin threw out the proposal, saying he had sent a telegram to Nemtsov's family.

"For the record: the State Duma refused to announce a minute of silence over Nemtsov's murder. Only I and Valery Zubov stood up, no one else," Gudkov wrote on Twitter, referring to another member of his party.

The parliament's upper house, the Federation Council, held a minute's silence for Nemtsov on March 4.

Investigators have revealed few details of the probe into Nemtsov's murder since detaining five suspects earlier this month who are accused of carrying out a contract hit.

The prime suspect in the killing, former Chechen police officer Zaur Dadayev, initially confessed to the crime but later told a member of the Kremlin's rights council he had been tortured into doing so.

The allegations sparked a fierce reaction from Russia's powerful Investigative Committee which accused the council of meddling in its probe and threatened to investigate its motives.

Investigators then refused a request by the head of the rights body to visit the suspects last Friday in the wake of the torture allegations, saying they were looking into the charge "in accordance with the law."

Putin's spokesman Dmitry Peskov on Tuesday said the president was being kept up to date on the investigation.