U.K. Prime Minister Keir Starmer and German Chancellor Friedrich Merz have signed a treaty that pledges to tighten defense ties.

"A comprehensive increase in the EU budget is unacceptable at a time when all member states are making considerable efforts to consolidate their national budgets," said Stefan Kornelius, spokesperson for Chancellor Friedrich Merz's government in Berlin late Wednesday. "We will therefore not be able to accept the Commission's proposal."