European leaders have agreed to strengthen joint measures against Russia after ceasefire talks with Ukraine failed to yield progress, British Prime Minister Keir Starmer announced on Friday.

Following the meeting in Istanbul, where the sides held their first direct talks in over three years, Starmer and leaders from France, Germany, and Poland spoke with US President Donald Trump and Ukrainian President Volodymyr Zelenskyy, as reported by Reuters.

Although the talks led to a major prisoner exchange, no breakthrough was made on a ceasefire. “The Russian position remains unacceptable,” Starmer said from the European summit in Albania. “We are now closely aligning our responses.”

French President Emmanuel Macron added that if Russia continues to reject a ceasefire, sanctions will be escalated and are currently being revised, Reuters reported.