Three countries under military rule have officially left West African regional bloc Ecowas, after more than a year of diplomatic tensions.

The withdrawal of Mali, Burkina Faso and Niger is a huge blow to Ecowas, which at 50 years old is considered Africa’s most important regional group.

The split was sparked after the three departing countries refused Ecowas demands to restore diplomatic rule.

On Wednesday Ecowas said it would keep its “doors open” to Mali, Burkina Faso and Niger, even though they have forged ahead with their own bloc, the Alliance of Sahel States (AES by its French acronym).

Ecowas – which stands for the Economic Community of West African States – was founded in 1975 in a bid to improve economic and political integration in West Africa.

Prior to Wednesday’s shake-up, the bloc had 15 members, including states like Nigeria, Ghana, Ivory Coast and Senegal.

Citizens of all Ecowas countries currently have the right to live and work in all member states, while goods can circulate freely.

Relations between Ecowas and the three Sahel countries have been tense since the military seized power in Niger in 2023, Burkina Faso in 2022 and Mali in 2020.

After the Niger coup, Ecowas imposed crippling sanctions on the country, such as border closures, a no-fly zone for all commercial flights and the freezing of central bank assets.

Ecowas also threatened to deploy its forces to Niger in order to restore democratic rule.

But this hard line merely strengthened the resolve of the three juntas.

Mali and Burkina Faso criticised Ecowas’ “inhuman” sanctions and vowed to defend Niger if the bloc intervened militarily.

After being suspended by Ecowas, the three states hit back by giving notice last January that they would withdraw in a year, meeting the timeline set by the bloc for states that decide to leave.

Negotiations between Ecowas and the juntas have taken place since then – but have failed.

The three countries accuse Ecowas of being too close to Western powers and have instead pivoted towards Russia.

According to the departing countries, they will now experience greater sovereignty and also independence from a force that has a foreign agenda.

But analysts say Niger, Mali and Burkina Faso may struggle outside the bloc – these are poor and landlocked countries whose economies depend on their West African neighbours.

While Ecowas works out the terms of its future relationship with the three countries, it says it will continue to recognise all passports and identity cards bearing the Ecowas logo held by citizens from Mali, Niger and Burkina Faso.

The countries will also remain in the bloc’s free-trade scheme.

Similarly, AES chairman, Mali’s military ruler Assimi Goïta, said last January that the right of Ecowas citizens to “enter, circulate, reside, establish and leave the territory” of the new bloc would be maintained.

Ilyasu Gadu, an international affairs expert and media consultant based in Nigeria’s capital Abuja, told the BBC: “The three junta leaders have taken steps to say: ‘Yes, we are pulling out of Ecowas but we want to maintain our relationships. We will not close our borders’ because they must have realised that if they do that, they would have shot themselves in the foot.”

West Africa observers are also concerned the withdrawal will worsen security in the region. The Sahel – the semi-arid region just south of the Sahara Desert that includes the three departing countries – is wracked with jihadist insurgencies and now accounts for “almost half of all deaths from terrorism globally”, a senior UN official said in April.

Ecowas was supporting Mali, Burkina Faso and Niger in their fight against the jihadists, but this help may now be rescinded, observers fear.

Although the juntas now receive weapons and mercenaries from Russia, the militants continue to inflict heavy casualties on both civilians and the armed forces.

Ecowas will lose 76 million of its 446 million people and more than half its total geographical land area.

There are also concerns the withdrawal will weaken both regional unity and cooperation in combatting insurgencies.

The split “worsens a legitimacy crisis of ECOWAS which has often failed people’s expectations in upholding the rule of law,” Ulf Laessing, head of the Sahel program at the Konrad Adenauer Foundation, told the Associated Press.

“That the three poorest member states decided to leave the bloc makes Ecowas in the eyes of its citizens look even more like a loser in this conflict.”

On Tuesday, some people in the three departing countries’ capitals took to the streets to celebrate the withdrawal.

But not everyone supports the juntas’ decisions.

Omar Hama from Niger said he wished the three countries had remained in Ecowas, while simultaneously belonging to the AES.

“I would have liked them to overcome their differences because we have a common space, same people with historical similarities and same economic realities,” he told the BBC.

Fatouma Harber, a journalist and blogger living in Mali, is worried that the change may eventually cause administrative and economic hassles for her and other citizens of the three countries.

“However, if the Alliance of Sahel States (AES) can really bring benefits for us, that would be an excellent thing,” she said.

Zabeirou Issa, who lives in Mali’s capital Bamako, took a firmer stance, saying: “Ecowas does not have any power, it is the Westerners who decide for the Ecowas leaders. Yes, I am very happy about the decision.”

In Ouagadougou, Burkina Faso’s capital, Cisse Kabore told the BBC she wanted her country to remain in Ecowas because now the region “will no longer be united as before”.

Last month, Ecowas said it would give Niger, Burkina Faso and Mali a six-month grace period for them to reconsider their withdrawal.

However, at a press conference on Wednesday, Ecowas Commission head Omar Alieu Touray said: “Any state can decide to come back in the community at any time.”

To consolidate their exit from Ecowas and strenghten their alliance, the three countries said they would begin circulating new AES passports on Wednesday.

They have also decided to join forces to create a 5,000-strong military unit to fight the jihadist violence that has plagued the nations for years.