Austrian Chancellor Karl Nehammer visited Moscow on Monday, marking the first time a Western leader has visited President Vladimir Putin since the start of Russia’s war on Ukraine.

The trip follows Mr. Nehammer’s visit to Ukraine’s President Volodymyr Zelensky in Kyiv on Saturday. He is set to meet Mr. Putin at the Kremlin around 4 p.m. local time.

Mr. Nehammer has faced criticism at home for his Moscow trip, just a week after reports first appeared about atrocities allegedly committed by Russian troops on civilians during their occupation of the Kyiv region.

Politicians from the chancellor’s own coalition warned that the Russian president could use the visit for propaganda. Mr. Nehammer said the trip was a risky mission but that diplomacy was now needed to end hostilities.

“Everything that can be done to help the people of Ukraine and stop the war must be done,” he said on Sunday.

Austria has traditionally close ties with Russia but has condemned alleged Russian war crimes in Ukraine.

Austrian officials said the trip was coordinated with the leaders of European Union institutions, with Turkish President Recep Tayyip Erdogan and with German Chancellor Olaf Scholz.

A spokeswoman for the German government welcomed Mr. Nehammer’s trip to Moscow and said Berlin supported his diplomatic initiative.

Dmitry Peskov, the Kremlin spokesman, said Monday that the talks between Mr. Putin and Mr. Nehammer would be focused on Ukraine, but the two leaders could also discuss Russian gas exports to Europe.

“The main topic will be the situation around Ukraine, but on the other hand, discussions on gas can’t be ruled out, since this topic is very, very relevant to the Austrian side,” Mr. Peskov said.

Over 80% of Austria’s gas imports come from Russia, and the country has ruled out sanctions that would hurt Mosco’s energy exports.

Austria’s model of neutrality is among those discussed as possible blueprints for Ukraine during negotiations with Russia. Moscow has made Ukraine’s neutrality one of the conditions of ending the war—a condition Ukraine has said it was willing to consider.

In a recent conversation with Mr. Scholz, Mr. Putin seemed to accept Austrian-style neutrality as part of a potential deal, a German official said.

A 1955 treaty provides Austria with security guarantees by Russia, the U.S., Britain and France, while at the same time Vienna invests in its own defense.

“The self-determined neutrality of Austria has been fully accepted by Moscow and that is clearly a model in the Ukraine talks, but the question remains who would offer similar guarantees to Kyiv,” Hans Mahr, a former Austrian official and analyst, said.