A week-long blaze at a recycling plant cost £20million – a company director has revealed as work resumes after a three-month shutdown.

Following the fire, more of Havering’s waste was sent to landfill, Cllr Stephen Kelly, a director at Shanks, in Creek Way, Rainham, added.

Normally, 34 per cent of the borough’s waste is recycled but Cllr Kelly said a “few per cent” more had to be buried after the fire.

The blaze in August saw more than 2,500 tonnes of household rubbish go up in smoke.

Firefighters from more than six stations had to be drafted in to tackle it.

But Cllr Kelly said that the cost would not be pushed onto residents.

“It’s not going to affect the borough,” he said. “That’s what we have insurance for.”

The council’s waste disposal costs initially rose due to more being sent to landfill.

But Cllr Kelly added: “We will recover all costs.”

Two out of three processing areas at the site are now up and running again. The blaze covered the area in black smoke.

It still isn’t known how the blaze started but it is possible that someone wrongly disposed of flammable material, said Cllr Kelly.

Staff at the site and nearby plants had done “wonderful” work to ensure “we came out of it very lightly”, he added.

There will be no “major changes” to the plant, he said, but the site’s safety is continually monitored and improved.

London boroughs were set a target in 2011 to cut their proportion of waste sent to landfill to 50pc by 2020.But Havering has already smashed the target and only buries 20pc.

Much is sold to Holland and the Baltic states for use as fuel, while a third is recycled.