France is preparing to evacuate its citizens from the West African nation of Niger because of anti-French sentiment following last week's coup.

It has said it will also help other European nationals to leave.

The coup has prompted demonstrations against the former colonial power, with the French embassy coming under attack.

It comes as the juntas in Burkina Faso and Mali warned that any forcible attempt to restore the ousted president would be seen as a declaration of war.

The two neighbours, also former French colonies, have both moved away from France and towards Russia, after staging their own coups in recent years.

Their warning marks a significant twist that could escalate the volatile situation in a region battling an Islamist militant insurgency.

Niger, which is rich in uranium, has been a key Western ally in the fight against jihadist extremism in the Sahel and both France and the US have military bases there.

After Mali's military leaders chose to partner up with the Russian Wagner mercenaries in 2021, France moved the centre of its regional counter-terror operations to Niger.

On Sunday, protesters outside the French embassy in the capital, Niamey, chanted "Long live Russia", "Long live Putin" and "Down with France".

They also set fire to the walls of the embassy compound.

The French foreign ministry said its evacuations would begin on Tuesday in view of this situation.

It said its decision was also influenced by the closure of Niger's airspace, which had made it impossible for French citizens to leave by their own means.

Italy's foreign minister also said Italian citizens were being offered the chance to leave Niamey on a special flight to Italy.

Earlier, France had welcomed the ultimatum issued on Sunday by the West African bloc Ecowas, giving Niger's junta a week to reinstate elected President Mohamed Bazoum, who has been confined to the presidential palace in Niamey.

Chad's President Mahamat Idris Déby was in Niger the following day, leading mediation efforts on behalf of the Ecowas and was pictured with Mr Bazoum.

These diplomatic moves prompted Burkina Faso and Mali to issue a joint statement threatening that if Ecowas intervened militarily, they would withdraw from the bloc and go to the defence of their eastern neighbour.

They said such an intervention would be disastrous and destabilising.

Burkina Faso, Mali and Guinea are all currently suspended from Ecowas following coups in recent years.

Ecowas's last major military intervention was in The Gambia in 2017 when Yahya Jammeh refused to step down as president after losing elections to Adama Barrow. After West African troops deployed, Mr Jammeh went into exile in Equatorial Guinea.

The regional body also sent troops to support Guinea-Bissau's government last year following a failed cop attempt there.

Niger's junta has not commented on the Ecowas demand, but vowed to defend the country from any "aggression" by regional or Western powers. It accused France of planning military intervention.

But on Monday evening, French Foreign Minister Catherine Colonna told French channel BFM TV the allegation was not true.

She suggested the coup, which has been welcomed by the shadowy Wagner group, could be an seen as an opportunity for Russia: "I am not sure that everyone in Niger sleeps with a Russian flag under their pillow. But it is possible that Russia tries to take advantage of the situation. It does it in other countries of the region. It's an hypothesis."

The situation in Niamey is reported to be calm on Tuesday as preparations for evacuations of Western citizens begin.

A crisis meeting is currently taking place at the French foreign ministry as it liaises with the embassy in Niamey.

According to the Reuters news agency, the evacuation plans will not impact Orano's operations in Niger as the French nuclear fuel company said most of its staff were Nigerien nationals.