Nigeria's president and head of the West African bloc ECOWAS, Bola Tinubu, has not ruled out military intervention in Niger, but believes diplomacy is the "best way forward" to resolve the crisis, his spokesman has said.

"No options have been taken off of the table," Tinubu's spokesman Ajuri Ngelale said on Tuesday — but Tinubu and other West African leaders favour diplomacy.

Tinubu weighed in for the first time since the soldiers behind the coup in Niger defied the bloc's Sunday deadline to reinstate elected President Mohamed Bazoum or face the possible use of force.

Meanwhile, efforts by ECOWAS and the United States to parlay with Niger's new rulers have made no headway ahead of a crisis summit in the Nigerian capital Abuja on Thursday.

The United States said it still held out hope for reversing the coup but was "realistic" a day after a top US envoy made no visible progress in an unannounced visit. "We do have hope that the situation will be reversed but at the same time, we are making clear, including in direct conversations with junta leaders themselves, what the consequences are for failing to return to constitutional order," State Department spokesman Matthew Miller told reporters.

Earlier, the soldiers who seized power in Niamey on July 26 blocked a mission by ECOWAS in the run-up to the summit. In a letter, the coup leaders said that public "anger" triggered by ECOWAS sanctions meant the delegation's safety could be at risk.

Path to dialogue

ECOWAS — the Economic Community of West African States — slapped trade and financial sanctions on Niger after rebel soldiers toppled Bazoum.

The bloc also gave Niger a seven-day ultimatum to reinstate Bazoum or face the potential use of force, but the coup leaders defied the warning.

A source close to ECOWAS said on Monday that military intervention was not being immediately envisaged and the path to dialogue still appeared open.

The bloc sought to send a delegation to Niamey on Tuesday ahead of the crisis summit due to be held in Abuja, the Nigerian capital, on Thursday.

But the coup leaders' letter, dated Monday, said, "The postponement of the announced mission to Niamey is necessary, as is the reworking of certain aspects of the (delegation's) schedule."

The schedule "includes meetings with certain personalities which cannot take place for obvious reasons of security given the atmosphere of the threat of aggression against Niger," it said.

US envoy visits Niger

ECOWAS is struggling with a cascade of coups that since 2020 has now hit four of its 15 members.

In Mali, Burkina Faso and now Niger, all of the takeovers have been fuelled by a militant insurgency that has claimed many thousands of lives, forced at least two million from their homes and dealt crippling blows to some of the world's poorest economies.

On Monday, Victoria Nuland, a veteran US envoy, met with the country's military rulers for more than two hours but came away empty-handed. She described her talks as "extremely frank and at times quite difficult".

She said she offered the coup leaders "a number of options" to exit the crisis and restore the relationship with the United States, which like other Western nations has suspended aid. "I would not say that we were in any way taken up on that offer," she told reporters before her departure.

Niger's new leader, General Abdourahamane Tiani, did not attend the meeting, and Nuland was unable to see Bazoum, who has been detained since July 26.

Warnings

The juntas in Mali and Burkina Faso have expressed solidarity with Niger, saying that any military intervention would be seen as a "declaration of war" against them.

Algeria, which shares a long land border with Niger, has cautioned against a military solution, which President Abdelmadjid Tebboune said would be "a direct threat" to his country.

Senators in Nigeria — the regional superpower and a major voice demanding tough action — have urged everyone to focus on the "political and diplomatic option." Bazoum, 63, was feted in 2021 after winning elections that ushered in Niger's first-ever peaceful transition of power.

He took the helm of a country burdened by four previous coups since independence and survived two attempted putsches before he himself was ousted.

His support was a key factor in France's decision last year to refocus its Sahel mission on Niger after withdrawing from Mali and Burkina Faso.

France has 1,500 troops in Niger, and the United States has 1,000 personnel, most of whom are deployed at two major air bases.

Nuland said she warned Niger not to follow Mali by bringing in Wagner mercenaries from Russia.

"The people who have taken this action here understand very well the risks to their sovereignty when Wagner is invited in," she said.