Germany’s would-be chancellor has attempted to win the support of the Greens for his proposed fiscal rule changes, offering to expand the scope of defence spending and demanding to know: “What more do you want from us?”

The outgoing parliament is meeting to debate the creation of a €500bn (£420bn) fund for infrastructure investment and radical changes in Germany’s borrowing limits in order to boost defence spending.

Friedrich Merz, whose conservatives won last month’s election and who is on the verge of becoming the new leader, wants to seal the funding deal before the new parliament convenes in less than two weeks. An expanded group of far-right and far-left MPs could oppose it in the new Bundestag, a “blocking minority” Merz is keen to avoid.