The U.S. and Russian defense chiefs spoke by telephone on Friday for the first time since May, according to a Pentagon spokesperson.

Defense Secretary Lloyd Austin and Russian Defense Minister Sergei Shoigu discussed “international security problems, notably the situation in Ukraine,” according to a readout posted by the Russian Ministry of Defense on Telegram Friday morning.

During the call, Austin “emphasized the importance of maintaining lines of communication amid the ongoing war against Ukraine,” said Pentagon spokesperson Brig. Gen. Pat Ryder.

This is only the second time the two have spoken since Russia’s February invasion of Ukraine. The first call was on May 13. During that conversation, Austin reportedly urged his Russian counterpart to consider a cease-fire, which Moscow ignored.

Before that May call, the two spoke on Feb. 18, six days before the invasion.

Friday’s call comes following days of Russian missile attacks on civilians in Ukraine, and as Vladimir Putin makes illegal claims to Ukrainian territory in the country’s east and south.