MPs and peers say pitting defence and welfare against each other risks losing public support for increased spending on the military

Senior Labour figures have warned that Rachel Reeves must find alternative ways to increase military spending rather than slashing welfare, saying it risks public support for investment in defence.

Pressure has been mounting from Labour backbenchers for the Treasury to urgently agree the defence investment plan (Dip) after George Robertson, a former Nato secretary general, said there was a “corrosive complacency” on defence funding.

But MPs and peers said they did not back calls by the opposition for defence investment to be funded by cuts to welfare spending – saying there were other ways to secure the funds. The chancellor is understood to have proposed increasing the budget by less than £10bn over the next four years amid concerns that any more would be unaffordable.

On Wednesday, Keir Starmer said he did not agree with the comments from Robertson, a former Labour defence secretary who co-authored a defence review for the government. The prime minister insisted defence spending was increasing rapidly.