PARIS — French Socialist presidential candidate Francois Hollande, facing off against resurgent Nicolas Sarkozy, looked to make up ground Thursday with vows to boost taxes on the rich.

In a three-hour appearance on France 2 public television, Hollande sought to cement his left-wing credentials with promises of tax hikes on the wealthy but also to steal some thunder from the right on the issue of immigration.

Hollande was keen to regain momentum after recent polls showed Sarkozy catching up in the race to win the two-round April-May presidential vote.

He said he would boost a "solidarity" tax aimed at the richest taxpayers, and would re-establish a previous Socialist-era ceiling that allowed direct taxes to be applied to up 85 percent of taxpayers' incomes.

He also reiterated his vow to introduce a 75 percent tax rate on incomes above one million euros ($1.3 million) and said the 85 percent ceiling would not apply to that tax.

He announced he would impose measures to collect taxes from French tax exiles in Switzerland, Belgium and Luxembourg, taking a page from Sarkozy who recently announced a capital-gains tax on French living abroad.

In the face of calls from Sarkozy and others on the right for France to tighten its immigration rules, Hollande denied claims he would allow for a mass regularisation of illegal immigrants.

He also said he would set up a special law enforcement brigade to fight international people-smuggling networks and hold annual debates in parliament to set the number of immigrants allowed into the country.

Hollande expressed confidence in his campaign despite his recent trouble in the polls.

"I have not strayed from the line I set since the beginning: coherence, consistency and confidence," he said, denouncing his opponents for running an "excessive" and "vulgar" campaign.

A poll this week for the first time showed Sarkozy pulling slightly ahead of Hollande and the latest poll, a CSA study released Wednesday, showed them equal with 28 percent support in the first round, to be held on April 22.

The same poll showed Hollande still winning the second round on May 6 with 54 percent, but that was two points down from its previous poll.

The Socialist is also looking to take on a challenge from Left Front candidate Jean-Luc Melenchon who has enjoyed a recent bump in the polls.

Firebrand Melenchon, representing a left-wing coalition including the Communists, surpassed the symbolic 10 percent mark in polls last week with virulent attacks on the financial world and European austerity policies.

The CSA poll saw him gain one point to hit 11 percent support.

The televised interview and debate was expected to be Hollande's last long media appearance before the campaign officially begins on March 20, after which broadcast media will be required to give all candidates equal air time.

Hollande also said he did not want to "scare" Europe's conservative leaders but was aware that they "don't like me very much".

Hollande has angered Europe's right-wing, in particular German Chancellor Angela Merkel, by vowing to renegotiate the EU's fiscal restraint pact.

"I am not here to scare them, even if I've understood that they don't like me very much, which is probably because I have positions that are different from theirs," he said.

Hollande said that, if he wins, "I will have to work with European leaders, but I wanted to be clear right from the start".

Merkel has openly backed Sarkozy while Conservative British Prime Minister David Cameron has wished his "friend" Sarkozy luck.