and Keir Starmer said Labor must change from a “protest party” to one that can win the elections, to help working people.
The Labor leader said he supports people’s right to strike, pointing to his pro bono work as a lawyer representing striking miners.
“Not just sentiment and a photo opp. I backed up my words with action,” he wrote in the Sunday Mirror.
Everywhere you look in Britain you see the toll of 12 years of Tory rule
It comes as Sir Keir tries to curb a spat with unions and the left wing of his party over his decision to sack Sam Tarry from the front bench after giving broadcast interviews from a picket line.
Sir Keir, who previously banned front benchers from joining strikers on picket lines, said he sacked Mr Tarry as shadow transport minister after booking himself into media programs without authorization and making up “on the hoof” policies in defiance of the “collective party “responsibility”.
But the move was met with outrage by the Labor left and unions, with Sharon Graham, Unite’s general secretary, saying she was “stunned” at Sir Keir’s approach to striking workers.
In his article, Sir Keir emphasized his immediate focus on getting his party to power, with a Labor government that can then bring change for unions and working people.
He wrote: “I fully understand why people go on strike to get better pay and better conditions. I support their right to do that.
“When I was a lawyer, I represented striking miners for free. Not just sentiment and a photo opp. I backed up my words with deeds.
“I now lead a Labor Party that wants to change lives and give” Britain the fresh start it needs.
“That means changing from a protest party to a party that can gain power — and then hand that power over to working people. I don’t apologize for that.”
The Labor leader also criticized the Conservatives’ track record in government.
“Everywhere you look in Britain you see the toll of 12 years of Tory rule,” he said.
“People work harder, but get less in return.”
He attacked the candidates vying to replace Boris Johnson as prime minister, saying: “Those responsible should hang their heads in shame.
“And as accomplices to Boris Johnson, that includes Rishi Sunak and Liz Truss. Just continuity candidates. Unable to provide the needed change.”
Sir Keir said Labor is on the side of people “angry and scared” at the prospect of skyrocketing energy bills.
If I were to talk to Keir right now, I’d say to him, ‘Which side are you on?
“Only in power can Labor bring about the changes that unions and working people want to see,” he wrote.
“This is not just our agenda, or the agenda of the unions. It is an agenda for the whole country.”
Ms Graham told The Mirror on Saturday: “If I were to talk to Keir right now, I would say to him: which side are you on? Because the reality is that if I closed my eyes, sometimes I wouldn’t know whether it was the Labor Party or the Tories speaking.
“This is one of the biggest crises facing workers – we try to defend them with every fiber of our being and the party that should repeat that in parliament is doing the exact opposite.
“I’m very disappointed – stunned, frankly – and I think it’s something that Labor needs to think seriously about.”
Tarry said he “absolutely” still thinks Sir Keir is the best person to become prime minister.
Joining another picket line at Paddington station in London on Saturday he called for a “fundamental reassessment” of the Labor Party’s relationship with the union movement and said it was necessary to show it was on their side.