Tony Blair and Ed Miliband
The former Labour leader quashed speculation that he is not behind Ed Miliband with the donation Getty

Multi-millionaire Tony Blair has put his money where his mouth is and quashed speculation that he is not behind Ed Miliband by donating more than £100,000 to Labour.

The former prime minister handed candidates £1,000 ($1,524, €1,378) for each of Labour's 106 target seats for the forthcoming general election.

The £106,000 donation is his biggest yet and is more than 14 times the amount he donated to Labour in 2008 when he handed the party £7,500.

"I know how hard it can be to raise money to fund a local campaign, but for you, in one of our 106 battleground seats, it is even more vital," Blair said.

"This is where the election will be won for Labour and that is why I am making a donation to all 106 campaigns."

The donation comes after the former Labour leader warned that a "traditional left wing party" would not win the next election.

He also stressed that Labour "succeeds best when it is in the centre ground".

"I am still very much New Labour and Ed would not describe himself that way, so there is obviously a difference there," he told The Economist.

But Blair played down the interview, which seemed to be an intervention into Miliband's leadership, and said he was "mis-interpreted" over the remarks he made to the weekly.

The prime minister's estimated wealth has garnered considerable speculation and last year he said the total figures is less than £20m.

Vanity Fair, who interviewed an anonymous spokesman for the former prime minister later that year, estimated that Blair is worth around £10m.

But the figure fails to take into account the statesman's property portfolio, which some estimate at more than £25m.

A Labour spokesman said: "This donation from a former leader who won three general elections for our party will help Miliband win again for Labour and for Britain on May 7."

The latest poll from YouGov, which questioned more than 1,500 voters between 3 and 4 March, put Labour and the Tories neck-and-neck (34% vs 34%), with Ukip on 14%, the Liberal Democrats on 8% and the Greens on 6%.