UKIP's deputy leader Nigel Farrage is to fight the late Eric Forth's Bromley and Chislehurst seat.
Mr Farrage told Gallery News today that he will make his announcement on Friday.
"I have had an invitation to stand from our local branch. It was passed unanimously. I will make my announcement on Friday."
According to sources close to Mr Farrage, his campaign on a 'Lend Me Your Vote' and 'New Labour or Blue Labour'.
"The source said, " Despite the 13,000 majority, he is convinced he can win it. It could be a major shock for all three major parties. He will spell out that he would not expect them to vote for him at a General Election - but he will appeal to the Conservative voters to send a shot across the bows of the Tory party.
"His message will be to lend him the seat until the next General Election to warn the Tories not to get too cosy on Europe, immigration and taxation."
Asked if he intended to stand, Mr Farrage told Gallery News, "I am positively thinking in that direction. I do not think the Conservative party or Bromley and Chislehurst Conservatives will choose someone in the mould of Eric Forth."
He said Mr Forth, whose funeral took place last week, was a 'signed up member' of the Better Off Out (of the EU) campaign.
"We would not have put up a candidate against Eric Forth at the next General Election. We do not believe that the Conservative will select a candidate who will maintain traditional party policies on Europe, tax and immigration - policies where there is nothing to choose between the three main parties.
"What I expect is that the voters will be offered a choice between New Labour and Blue Labour.
"I will be making a statement on Friday and it will be surprising if I do not accept the unanimous invitation of the Bromley party to stand as their candidate."
Mr Farrage said he expected the Conservatives to select their candidate
on Saturday, the writ to be moved on Thursday next week and for the
by-election to be held on June 29.
The result at the 2005 General Election:
Eric Forth, Conservative 23,583 (51.1%)
Rachel Reeves, Labour 10,241 (22.2%)
Peter Brooks, Liberal Democrat 9,368 (20.3%)
David Hooper, UK Independence Party 1,475 (3.2%)
Ann Garrett, Green Party 1,470 (3.2%)
Conservative majority: 13,342
Source: Gallery News, House of Commons (Wednesday 31 May)