U.S. Secretary of State Marco Rubio and his Russian counterpart will meet Thursday in Malaysia for what could be a testy conversation as tensions between the countries rise over Moscow’s increasing attacks on Ukraine and questions about whether Russia's leader is serious about a peace deal.

Sweeping tariffs set to be imposed by President Donald Trump next month may overshadow his top diplomat’s first official trip to Asia this week — just as the U.S. seeks to boost relations with Indo-P...