Chad's interim President Mahamat Idriss Deby kicked off his presidential campaign on Sunday for an election next month meant to end three years of military rule on a promise to strengthen security and boost the economy.

Deby's government is one of several juntas that seized power in West and Central Africa since 2020, drawing concerns of a democratic backslide.

Chad is the first of these to organise elections despite regional and international pressure to swiftly hand power back to civilians.

"Today we are at the final turn on the road to constitutional return," Deby told a large crowd gathered in scorching weather at the high-security event in Chad's capital N'Djamena.

"You know me, I am soldier and I hold my promises," he said, barely visible behind a barrier of body guards crowding the podium.

"We will strengthen internal security to guarantee peace and stability in our country," he said.

Deby seized power in 2021 when his long-ruling father Idriss Deby was killed on the front line against rebels in the north.

He initially promised a return to civilian rule within 18 months. But his government later pushed elections back to 2024 and allowed him to stand for president.

The delay triggered protests that were violently quelled by security forces with around 50 civilians killed.

"Governing Chad is not easy. It is easy to criticise from afar on social media," he said.

Deby confirmed his intention to run at the start of March. The announcement was made days after opposition politician Yaya Dillo was killed in an exchange of gunfire with security forces, raising concerns about conditions for the upcoming poll.

Forensic experts have since said Dillo was likely shot at point-blank range.

The nine other presidential candidates include Chad's recently-appointed Prime Minister Succes Masra, a staunch opponent of the junta.

It is the first time is the Central African country's history that a president and a prime minister will face each other in a presidential poll.

The first round of voting is scheduled to take place on May 6 and the second round on June 22, with provisional results due on July 7.

At the inauguration speech, Deby mentioned plans to modernise agriculture, boost industry, build more paved roads and provide reliable electricity.

Over 40% of people live below the national poverty line in Chad, which is grappling with an influx of refugees fleeing conflict in neighbouring Sudan that is worsening food insecurity in the country.