German chancellor Angela Merkel said she raised concerns with Russian president Vladimir Putin about a reported violent crackdown on homosexuals in Chechnya during a meeting in Sochi on Tuesday.

"I asked President Putin to use his influence to protect these minority rights," Mrs Merkel told reporters following a tense round of talks with the Russian president.

Mrs Merkel, who arrived in Sochi on Tuesday afternoon for her first visit to Russia in two years, said that she raised the issue along with other human rights concerns, including police breaking up anti-Kremlin protests and a Supreme Court ruling last month banning the Jehovah's Witnesses religious group as extremist.

"I have in my talks with the Russian president indicated how important the right to demonstrate is in a civil society and how important the role of NGOs is," Mrs Merkel said.

Mr Putin denied that Russian police had violated protesters' rights by arresting them, and fired a barb back at his European counterparts.