The removal of 30,000 cubic metres of sediment from the river is a process that “requires environmental care” and time to get the equipment, which does not exist in government departments, João Matos Fernandes said.

On 24 January, a large amount of foam appeared in the river Tagus, leading to the collection of samples that detected the presence of high amounts of cellulose.

The existence of about 30,000 cubic metres of sediment meant it had to be removed and work has already begun.

The minister said specific equipment was being acquired for this operation such as kilometre long suction hoses, which “nobody had”.