Germany's would-be next chancellor, Friedrich Merz, won lawmakers' approval to loosen strict debt rules for higher defense spending as doubts mount about the strength of the trans-Atlantic alliance.

Germany's parliament approved plans for a massive spending surge on Tuesday, throwing off decades of fiscal conservatism in hopes of reviving economic growth and scaling up military spending for a new era of European collective defence.

Germany’s chancellor-to-be Friedrich Merz has agreed a deal with the Green party to inject hundreds of billions into the country’s defence sector and ageing infrastructure, according to two people with knowledge of the discussions.