After several hours of debate, the members of parliament voted 131 in favour and 31 against.
Some activists have been campaigning against the presence of foreign troops, branding them occupiers who threaten national sovereignty.
However, the outcome of the vote was in little doubt with the parliament in Niamey totally dominated by allies of President Mohamed Bazoum.
Niger has the support of several Western countries in its battle against Al-Qaeda and terrorist jihadists, including the United States and France, which have military bases in the capital and the Agadez region in the north.
“Entering into new partnerships in no way calls into question our sovereignty over the national territory,” said Prime Minister Ouhoumoudou Mahamadou.
The agreed text “unequivocally indicates the openness of our country to conclude alliances” against jihadists, he said.
Niger “is practically surrounded by armed terrorist groups”, the head of government said.
He also referred to the ongoing withdrawal of the French anti-jihadist Barkhane force and the smaller Takuba force of European special forces from neighbouring Mali.
The prime minister opened the door to increased collaboration with France, in particular.
According to the government document handed to MPs, the current situation requires Niger and other countries to commit to “an effective fight against terrorism, in the framework of bilateral or multilateral cooperation, either current or in the future.”
“The special forces of friendly countries will be deployed… (and) installed on the territories of members of ECOWAS (Economic Community of West African States) facing the threat.”
These include Benin, Ghana, Niger and Ivory, the document stated.
US and French special forces are already operational in Niger, which has declared itself ready to host more.
But their possible deployment in the other countries has not been officially mentioned previously.
According to the document, in Niger, “which already houses foreign troops bases, new sites will be set up nearer the theatres of operation” in Mali, where multiple jihadist groups operate.
“The locations and operational methods” of these forces will be discussed with Niger’s military hierarchy, it stated.
There was opposition to the parliamentary vote on Friday, but it failed to carry the day.
“We cannot give the government a blank check,” said opposition parliamentarian Soumana Sanda, while another mentioned “grey areas”.
France is reconfiguring its anti-jihadist forces in the Sahel after its relationship with Mali broke down following a military coup in August 2020.
Germany, which runs a logistics outpost in Niamey, has set up a centre close to the border with Mali to train Nigerien special forces.
Italy and Canada are also involved in special forces training.
The poorest country in the world according to the benchmark of the UN’s Human Development Index (HDI), Niger is facing two jihadist insurgencies.
One is unfurling in the southwest of the country, coming from neighbouring Mali, while the other is in the southeast, from Nigeria.
Criticism of the presence of foreign forces prompted Bazoum to announce in February that he would ask parliament to agree on any new “arrangements” with foreign partners to tackle the jihadists.