French President Emmanuel Macron formally announced Thursday that he will run for a second term in April's presidential election.

"I am seeking your trust again. I am a candidate to invent with you, faced with the century's challenges, a French and European singular response,'' Macron said in a letter to the French people.

The letter published online by numerous news sites ended months of speculation and signaled the start of the election campaign.

If he succeeds, he would be the first French leader to win a second term in office for two decades.

The first round of the presidential vote would take place on April 10 and the runoff, if necessary, was scheduled for April 24.

Macron's most significant challenge from the right

Polls show Macron as the contest's front-runner.

His main challengers are far-right candidate Marine Le Pen and Eric Zemmour and conservative candidate Valerie Pecresse.

They accuse him of being lax on immigration, soft on crime, and slow to defend French culture. 

The Ukraine war has, however, upended the campaign and has as put Macron at the center of the news agenda as he has held several phone calls with Russian President Vladimir Putin.

It also changed the focus to foreign policy rather than the domestic issues favored by his opponents.

"Of course, I will not be able to campaign as I would have liked because of the context," Macron wrote, vowing to "explain our project with clarity and commitment."

Macron sought a mandate to steer the eurozone's second-largest economy through the fallout of Russia's invasion and the COVID-19 pandemic.

"I am a candidate to defend our values that are threatened by the disruptions of the world," he added.

Macron also faced critics on the left

Macron became France's youngest-ever president in 2017.

He changed the economy to boost job creation and cut taxes on businesses. He also called repeatedly to make the European Union stronger in foreign policy terms.

However, critics said his policies threatened the French welfare state.

The anti-government yellow vest protest movement started with demonstrations against a planned fuel tax hike and quickly spread into a broader campaign against economic injustice. For months, weekly protests across the country often degenerated into scattered violence.

Macron admitted on Thursday, "We have not achieved everything," adding that he would do some things differently,

His popularity in recent months has remained relatively stable, with an approval rating hovering around 40% 

lo/rt (AFP, AP, Reuters, dpa)