The Security Council condemned Monday's attacks on two UN camps in Mali, which resulted in the deaths of one UN peacekeeper, a Malian soldier and a member of the Malian gendarmerie, along with six Malian contractors.
“The Secretary-General stresses that attacks targeting United Nations peacekeepers may constitute war crimes under international law,” a spokesperson for UN Secretary-General António Guterres said in a statement.
The day before, gunmen killed 18 people in an attack on a restaurant in Burkina Faso's capital, Ouagadougou.
Guterres expressed support for efforts of the G5 nations - Burkina Faso, Chad, Mali, Mauritania and Niger - to "combat terrorism and violent extremism" in the Sahel region.
All-African Sahel force planned
This counter-terrorism force comprising the five Sahel countries most exposed to armed Islamist attacks will not be up and running until this autumn, according to French President Emmanuel Macron.
It is intended to work alongside France's Barkhane force and the UN's Minusma.
But the Mali and Burkina Faso attacks have added to the urgency.
"These criminal acts underline the importance and urgency of creating a joint force between Sahelian countries with the help of the international community," Mali's UN ambassador Issa Konfourou told delegates at the UN Security Council.
Mali, Burkina attacks may not force UN's hand
"There's some need for a military option in the sense that we have jihadist movements that are still very active," Yvan Guichaoua, a lecturer at the Brussels School of International Studies, told RFI.
Whether the attacks in Burkina Faso and Mali will be enough to jolt the G5 force into action is another matter.
"Sadly, I think it's very unlikely," Sean Smith, a west Africa analyst at risk firm Maple Croft in London, told RFI.
"Firstly, the UK does not consider the Sahel to be a key strategic area. Meanwhile, in the US you have a president who's made it very clear he's not willing to sanction extra funds for UN peacekeeping missions."
That creates a budget short fall.
An estimated 400 million euros is necessary to get the G5 force of 5,000 troops off the ground.
So far, the European Union has promised 50 million euros and France, which has been leading the call for a G5 force, has pledged a further nine million, but both the US and the UK have made it clear that they are not willing for the UN to finance the mission, despite the Security Council giving it its approval.
Making up the numbers is "going to be quite a tough avenue for the Sahelian countries to pursue", reckons Smith.
Some experts argue the Sahel countries should not have to go it alone.
"If Western countries expect the Sahel to make an effort to try and tackle these security challenges and reinforce the security of the whole of west Africa, they're also going to have to chip in," argues Paul Melly, an associate fellow at Chatham House in London.
Chad on its way out
President Idriss Deby of Chad, which possesses the region's most capable military, has threatened to pull his country's troops out of all African peacekeeping operations and not join the G5 force because of the lack of financial support.
"Chad has been at the forefront of the fighting in northern Mali ever since operation Serval was deployed in 2013," explains Smith.
"As one of the key components of the UN peacekeeping mission in Mali, Chad is well placed to hammer home the cause for additional funds," he says.
The country has been hit by economic crisis, exacerbated by low prices for its main source of revenue, oil.
Budget concerns aside, questions linger over the effectiveness of a military response, particularly in the light of the sheer geographical challenge of policing such a vast and sparsely populated region.
In northern Mali - the epicentre of the jihadist threat - "it can take easily 10 or 11 hours to drive from Bamako to as far as Mopti and then from there onto Gao another 24 hours," says Paul Melly.
Beyond a military response
"When we look at the origins and what breeds militant activity, there’s more than just a military response," argues Yvan Guichaoua.
“You still have the problem that there are a number of armed groups driven both by jihadist ideology but also by money from drug trafficking for example," adds Melly.
An effective political process is needed to weaken the pull of poverty that drives recruitment, he says.
In Niger, however, the government of Mahamadou Issoufou has succeeded, if not in eradicating the jihadist threat, at least in keeping it at bay, thanks to what Guichaoua describes as "discreet diplomacy".
"There's a daily monitoring of people tempted by the jihadist adventure by local communities," he says. "There's networking done through local figures that contribute to maintaining the social cohesion in these countries."
Controversially, he argues that cohesion is also maintained through the profits of drug trafficking, which the G5 force is also meant to tackle.
"Some of these jihadis that are active also belong to a political economy, they are embedded in local communities."
A heavy-handed approach may not be compatible with this old-fashioned way of bringing about peace in this part of the world, Guichaoua reckons.
Taking time to find funding and to understand the complex dynamics in the region may in the end outstrip the temptation to rush the establishment of a G5 force.