French troops killed Moroccan Ali Maychou of the Group to Support Islam and Muslims (GSIM) in Mali last month, Defence Minister Florence Parly told AFP aboard a government plane as she returned from an official visit to the region.

He was "the second most-wanted terrorist in the Sahel, including by the Americans", after GSIM's number one Iyad Ag Ghaly, she said.

Comprising several jihadist groups linked to al-Qaeda in the Islamic Maghreb (AQIM), the GSIM has claimed responsibility for the biggest attacks in the Sahel since its official launch in 2017.

Ag Ghaly is a Tuareg Malian who has been involved in militancy for nearly three decades.

Mali's army has been struggling to contain the Islamist insurgency despite help from France, African neighbors and the United Nations.

A string of deadly assaults has underscored the fragility of a region where jihadist violence has claimed hundreds of lives.

In the latest attack, claimed by Islamic State-allied militants, gunmen on Friday shot dead 49 Malian troops at an army base near the border with Niger.

Over the weekend, two more Malian soldiers and a French soldier were killed.

France, whose 4,500-strong Barkhane force has been in the Sahel since 2014, has been trying to convince European partners to boost military assistance.

Earlier Tuesday, Parly acknowledged the security situation was "clearly difficult" but said France was nearing a breakthrough in the talks.

"By 2020, special forces from European countries will be deployed in Mali alongside the French special forces to pass on exceptional know-how" to Mali's army, Parly said during a visit to the northern city of Gao.

She added that around a dozen countries had been approached to join the unit -- to be named "Takuba", which means "sabre" in the Tuareg language -- and had received encouraging replies.

Participation is conditional on votes in national parliaments but Parly said she was "optimistic".

Efforts to boost the European security presence in the region comes as continuing attacks have raised questions over the ability of the Malian army and its foreign backers to take control of the situation, as well as protests against international forces.

- Instability and protest -

Ali Maychou was killed during the night of October 8 with the help of Malian troops and US support, Parly said.

He joined AQIM in 2012 before co-founding GSIM with Iyad Ag Ghaly and masterminding its expansion in the Sahel.

"It's very important to profoundly disorganise these movements but that doesn't mean that these movements will self-destruct," Parly said.

Northern Mali fell into the hands of jihadists in 2012 before the militants were forced out by a French-led military intervention.

But the jihadists have regrouped to carry out hit-and-run strikes in violence that has spread to central Mali.

A month ago, some 40 troops were killed near the Burkina Faso border.

Mali's President Ibrahim Boubacar Keita has said Friday's attack shows the help of foreign forces is "necessary more than ever".

MINUSMA, the 13,000-strong UN peacekeeping mission in Mali, helped the army build the Indelimane base last year, along with French soldiers.

The G5 Sahel, a five-nation joint taskforce set up in 2014 to tackle the jihadist threat, is also active in the region. It comprises troops from Burkina Faso, Mali, Mauritania, Niger and Chad.

But the ongoing instability has stirred protests.

In mid-October, hundreds of demonstrators set fire to tyres and ransacked UN supply containers outside a MINUSMA military camp in Sevare, near the central Malian city of Mopti.

There have also been several protests against foreign troops in Niger since the beginning of the year.