Labour will switch to an “incumbency first” model to protect MPs at the next election rather than targeting seats, the deputy leader, Lucy Powell, has told Labour MPs.

Powell said the party would support MPs to become “leaders in their communities” and learn how to benefit politically from changes made by the government, which MPs have so far gained little credit for.

But she also told MPs in the first parliamentary Labour party (PLP) meeting of the year that they needed to stop infighting amid continued discontent with Keir Starmer’s leadership.

MPs will be offered workshops by organisers in Labour HQ on how to “take credit” for improvements in the local area or for policies directly helping constituents that have been implemented by the Labour government, including frozen rail fares, local community and high street funding and the warm home discount extension.

“It’s a big switch organisationally and politically,” a Labour source said. “There’s tools and training the party is providing but Lucy and Anna Turley [the Labour party chair] are leading some political work about what else is needed and how MPs can support and share best practice.”

Labour HQ and No 10 have made significant overtures to disgruntled backbench MPs over the past few weeks in an effort to shore up Starmer’s position and rebuild a semblance of unity in the PLP.

MPs have been routinely invited to see the prime minister – including receptions at his country retreat, Chequers – and backbenchers have been name-checked publicly by the chancellor and No 10 for campaigning for measures that were adopted in the budget or for lobbying for the U-turn on the farming inheritance tax changes.

At the PLP meeting on Tuesday, Powell said the government needed to speak more directly about its achievements and said that “dark forces” did not want a Labour administration to succeed.

“We’ve got a big argument to make and win. That Labour is on the side of ordinary people addressing the cost of living crisis, rewiring the country in the interests of the many not the few, taking on the vested interests, holding the powerful to account,” she said.

“With the budget, with the flagship changes coming in in the first half of this year, we have a stronger Labour story to tell: better rights at work, stronger protections for renters, putting more money in people’s pockets, lifting children out of poverty, fixing the NHS and public services on the mend after Tory austerity.”

Powell, who criticised some aspects of Starmer’s leadership during her campaign to be deputy, gave her explicit backing to the prime minister.

“We all need this government, led by Keir, to succeed, to show that progressive mainstream politics works. Our fortunes hang or fall together. Politics is a team sport. We are all leaders of that story, not commentators about it. If we fail, it’s Reform who win and our communities that lose,” she said.

“Politics is painted in primary colours and our colour is red. We don’t get Labour governments very often – there are lots of powerful forces that want to keep it that way. Let’s use it and bring the lasting change people voted for.”