Ukraine’s interior minister says 30 pro-Russian insurgents and four soldiers have been killed in the eastern city of Slovyansk as Ukraine continues an assault to reassert control. Ukraine has also sent an elite national guard unit to the southern port city of Odessa, where 46 people died Friday in clashes between nationalist and pro-Russian forces. White House spokesperson Jay Carney condemned the violence on Monday.

Jay Carney: “The events in Odessa dramatically underscore the need for an immediate de-escalation of tensions in Ukraine. The violence and efforts to destabilize the country must end. And we again call for the immediate implementation of the commitments made in Geneva on April 17th.”

White House Pressures CEOs Not to Attend Talks in Russia

Tensions between Russia and the United States over the Ukrainian crisis continue to increase. On Monday, the head of U.S. air forces in the Pacific reported an uptick in activity by Russian planes and ships in the region, including flights by Russian aircraft to the coast of California. The Obama administration, meanwhile, has successfully pressured the heads of many top corporations not to attend an upcoming economic forum in Russia. Cabinet members including Treasury Secretary Jack Lew and Commerce Secretary Penny Pritzker have reportedly been personally calling executives, urging them not to attend.