Marine Le Pen to run as presidential candidate in France.

French far-right leader Marine Le Pen has obtained the backing of 500 elected officials required to be a candidate in the April-May presidential election, The Telegraph reported.

"I have my 500 signatures and therefore I will be a candidate in the presidential election," Le Pen was quoted as telling Reuters.

A failure by Le Pen to gather the requisite support by March 16 could have rocked the election race with French far-right voters likely to have switched support to conservative President Nicolas Sarkozy, who is behind Socialist Francois Hollande in most opinion polls.

Le Pen - a charismatic speaker who has won a strong following since she took over the National Front leadership from her father Jean-Marie Le Pen in January 2011 - is running third in polls but with too low a score to seriously threaten Hollande or Sarkozy's chances of facing each other in a May 6 runoff.

The former lawyer has shifted from her party's traditional anti-immigration focus and is campaigning for France to exit the euro and erect protectionist barriers. She will hold a news conference later on Tuesday to announce that she is formally in the race.

Sarkozy leads Hollande for the first time in an opinion poll on Tuesday for round one of the election, but is still shown losing in the second round. The Ifop/Fiducial poll put support for Sarkozy at 28.5 percent in the first round on April 22, up from 27 percent at the end of February. Support for Hollande slipped to 27 percent, from 28.5 percent, the poll showed.