Lactalis, one of the world's largest dairy groups, had to recall 12 million tins in France and around the world due to the contamination, in a scandal that hit the reputation of France's strategic agri-business industry in overseas markets.

"The tower number 2 has resumed since Sunday for test phases. We want to check, control, inspect, analyse to make sure that everything is compliant," a Lactalis spokeswoman said.

"Since Sunday the results have been compliant, which is a rather positive step," he said.

The plant had been halted since December after discovering the contamination in baby milk produced in the production tower number 1, which the group permanently shut due to the outbreak.

None of the products made at the plant will be sold on the market before farm ministry approval, the spokeswoman said. Output is limited to powder milk for adults for the moment.

More than 200 babies in France have been contaminated with Salmonella Agona since 2005, including 38 between mid-August and December last year, as well as 25 between 2006 and 2017 and 141 in 2005, said the Institut Pasteur, a French organisation that monitors micro-organisms and diseases.

Lactalis CEO Emmanuel Besnier said in February that Lactalis could have been producing salmonella-tainted baby milk at the factory in Craon since 2005.

The crisis was likely to cost the company hundreds of millions of euros, he said.

It also hit French supermarket chains such as Leclerc, Auchan, Carrefour, and Systeme U which have all acknowledged that some of the baby milk remained on their shelves after the recall.

(Reporting by Pierre-Henri Allain and Sybille de La Hamaide; Editing by Edmund Blair)