Ed Miliband has dismissed the latest criticisms of his leadership as "Westminster tittle-tattle" as he promised to make Labour the party of society's "grafters".
Mr Miliband used a keynote speech to launch a twin-pronged attack on both excesses in the boardroom and abuses of the benefit system.
He suggested companies could be required to include a staff representative on their remuneration committees while people who were in work could be given priority in the allocation of council housing.
But after a weekend dominated by reports of unrest among Labour MPs and claims of a continuing rift with his older brother David, whom he defeated for the leadership, he was again forced to defend his own performance as leader.
In response to repeated questions by journalists, he said that such matters were of no interest to ordinary voters.
"Ordinary people up and down this country inhabit a different world. People aren't interested in who said what to whom in the Labour Party," he said.
"I am here because I was elected by my party. The gossip and tittle-tattle of Westminster is irrelevant to most people's lives."
The latest wave of speculation about his leadership was sparked by an unauthorised biography by Mehdi Hasan and James Macintyre which alleges he and his brother were barely on speaking terms after falling out as a result of last year's leadership contest.
David Miliband was forced to issue a statement, insisting that he stood "fully behind" his brother and urging the party to do the same.
Speaking at a south London community centre, Ed Miliband insisted they talk "all the time" and dismissed suggestions that he lacked his brother's wholehearted support.
