Angela Merkel has asked Vladimir Putin to help protect gay rights in Chechnya, amid allegations homosexuals there have been persecuted, tortured and even killed.
In her first visit to Russia in two years, the German Chancellor raised the alleged capture and torture of more than 100 people earlier this year after talks at the Black Sea resort of Sochi.
She told reporters: "I asked President Putin to use his influence to protect these minority rights."
Moscow has so far backed the Chechen government's denials over the brutal campaign, saying it had "no information" to support research by journalists and human rights groups.
But Mrs Merkel demanded Moscow properly investigate the allegations and ensure that LGBT people are fully protected in the territories and elsewhere.
Homophobia is widespread in Russia and Chechnya, a mainly Muslim region run by Ramzan Kadyrov, an authoritarian leader with a notorious private militia who is loyal to President Putin.
Mrs Merkel also called for freedom of assembly to be protected after Russian riot police arrested protesters demonstrating against the persecution.
"It's important to have the right to demonstrate in a democracy, and the role of NGOs is very importance," Mrs Merkel said.
Mrs Merkel urged Mr Putin to protect religious rights, too, especially those of the Jehovah's Witnesses church, which was recently banned in Russia for being an extremist organisation.
Relations between the two nations have been strained over Syria and Russia's annexation of Crimea from Ukraine, with the German Chancellor calling on Russia to guarantee repeatedly failed ceasefires in both wars.
In Ukraine, Russia supports separatist rebels fighting the EU-backed Kiev government, while it is allied with President Bashar al Assad in Syria.
Mr Putin claimed his government condemns the use of chemical weapons by any party in the conflict and called for an investigation.
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"Those guilty must be found and punished, but this can be only done after an impartial investigation," he said, adding that only the United Nations can find a lasting peaceful solution.
Mrs Merkel said she wanted to "keep trying to find solutions" to global problems and that Russia has an important role to play.