LIVE: Obama's Statement On Ukraine And Iraq...

President Barack Obama is delivering a statement from the White House briefing room.

His statement will come amid a day of significant escalation in the crisis in Ukraine, as Ukraine's president accused Russia of sending troops across the border to fight with pro-Russian separatists in Ukraine's southeastern regions.

Obama is also scheduled to meet Thursday afternoon with members of his National Security Council, as well as Vice President Joe Biden, on a strategy to further confront the extremist group calling itself the Islamic State (also ISIS or ISIL) in Iraq and Syria. A White House official said no new decisions are expected on how to proceed Thursday.

The U.S. conducted five additional airstrikes against the group in Iraq on Thursday, according to U.S. Central Command. The airstrikes destroyed a Humvee, a tank, four armed vehicles, and a construction vehicle, as well as severely damaging an ISIS checkpoint. Over the past three weeks, the U.S. has conducted 106 airstrikes against ISIS targets in Iraq.

Obama is weighing a broader offensive against the extremist group after it brutally murdered American journalist James Foley. Obama's secretary of defense, Chuck Hagel, and his top military brass have suggested ISIS needs to be confronted in Syria as part of any plan to contain the group.

The escalation in Ukraine, meanwhile, has sparked international outrage after Ukrainian President Petro Poroshenko accused Russia of sending troops across the Ukrainian border to fight with pro-Russian separatist rebels.

United States Ambassador to the United Nations Samantha Power lashed out at Russia in an emergency meeting of the U.N. Security Council on Thursday. She accused them of "outright lies" and a campaign of manipulation.

"They have manipulated, obfuscated, and outright lied," Power said. "The mask is coming off."

The emergency meeting of the security council was called after Ukrainian President Petro Poroshenko said Russian troops were fighting on the side of separatists in Ukraine and were advancing in the southeast region of the country. NATO subsequently echoed his allegations.

Ukraine's defense council said Russian troops are leading a separatist counteroffensive in the east, bringing in tanks and using artillery from inside Ukrainian territory.

A Russian-backed rebel leader said that at least 3,000 to 4,000 Russian troops were fighting inside Ukraine.

This post will be updated when Obama speaks.