David Miliband has dismissed ongoing speculation about possible tension with his younger brother Ed Miliband, declaring: "The comparison that counts is Ed against David Cameron, not Ed against me."
The former Labour Foreign Secretary endorsed his brother's position as Opposition Leader, telling BBC One's The Andrew Marr Show: "I think Ed is giving strong leadership."
Asked if he would be returning to frontline politics, Mr Miliband replied: "I feel I'm on the frontline, not on the front bench."
Mr Miliband, who lost out to his younger sibling in the Labour leadership contest in 2010, indicated he would remain as an MP representing South Shields.
Asked if he would stay in politics and stay in the House of Commons, he responded: "I've said that.
"My commitment is to fight for these people, because they need a Labour MP, but the truth is they need a Labour Government too."
He added: "I want to be part of the Labour team on the frontline, even if I'm not on the front bench."
Mr Miliband appeared not to rule out a possible change of role in the future but dismissed discussion about any existing rivalry with his brother.
He said: "I keep a watching brief on this, I said to you two years ago I think on this programme, I thought I didn't want a soap opera, I didn't want permanent invidious comparison.
"The comparison that counts is Ed against David Cameron, not Ed against me."
He added: "I think that the decision I took has actually been proven right, I think Ed is giving strong leadership. I think that I am refreshing myself, I'm learning, I'm engaging in a different kind of politics."