By Noah Rayman
September 4, 2014

The United States and Britain will “not be cowed” by Islamist militants in Iraq and Syria who have killed two American journalists, the leaders of both nations said Thursday.

Ahead of a NATO summit in Wales that began Thursday, President Barack Obama and British Prime Minister David Cameron published a joint article in the Times of London saying they will “confront” the militant group Islamic State of Iraq and Greater Syria (ISIS), and calling for international action to address security threats around the world.

“If terrorists think we will weaken in the face of their threats they could not be more wrong,” they wrote. “Countries like Britain and America will not be cowed by barbaric killers. We will be more forthright in the defence of our values, not least because a world of greater freedom is a fundamental part of how we keep our own people safe.”

The NATO summit, which is formally scheduled to address the drawdown in Afghanistan and the conflict in Ukraine, comes days after the ISIS released a video depicting its beheading of a second American journalist.

Obama and Cameron also called for NATO to increase pressure on Russia, which Western officials say is meddling in the conflict in Eastern Ukraine between Kiev and pro-Russian separatists.

“With Russia trying to force a sovereign state to abandon its right to democracy and determining the course of its future at the barrel of a gun, we should support Ukraine’s right to determine its own democratic future and continue our efforts to enhance Ukrainian capabilities,” they wrote.

Write to Noah Rayman at noah.rayman@time.com.

SPONSORED FINANCIAL CONTENT

Read More From TIME

EDIT POST