Niger says it will close illegal migrant camps in the north of the country after 92 people who died of thirst were found in the Sahara.
All those involved in trafficking migrants would be "severely punished", the government said.
The bodies of 52 children, 33 women and seven men were discovered after two trucks carrying them broke down on the way to Algeria.
Niger lies on a major migrant route between sub-Saharan Africa and Europe.
The government announced the plan to close illegal camps in northern Niger - which it referred to as "ghettos" - in a statement broadcast on television in Niger.
The migrants would be handed over to international aid agencies and the traffickers brought to justice, said the government statement.
"This tragedy is the result of criminal activities led by all types of trafficking networks," it said.
'Voluntary' repatriation call
The statement said Prime Minister Brigi Rafini would visit the southern district of Kantche, where most of the dead are thought to have come from, to present to their families the "condolences of the nation wounded by this tragedy".
Niger is observing three days of mourning, with flags outside public buildings flying at half mast.
Foreign Affairs Minister Mohamed Bazoum told the BBC that about 5,000 African migrants were currently stranded in illegal camps in the northern town of Agadez alone.
Having paid large sums of money to traffickers, these migrants are waiting to cross hundreds of kilometres of desert into Libya or Algeria, says the BBC's West Africa correspondent, Thomas Fessy. Many seek a better life in Europe.
The head of the International Office for Migration in Niger, Abibatou Wane, welcomed the announcement by Niger's government, but warned that migrants could only be repatriated to their home countries on a voluntary basis.
The bodies of 87 people, thought to be migrants, were discovered in the Sahara desert in the north of Niger on Wednesday.
Another five from the same convoy had been found several days earlier by the army.
Some of the dead migrants were found only about five kilometres from a well.