Bakers have been hit by riots and looting in London and around the UK, with losses expected to cost millions.

Greggs chief executive Ken McMeikan said it was monitoring the situation nationwide, closing shops where trouble was expected. In riots on Monday its Peckham shop was burned out and its Enfield shop looted. Other shops had not been able to open as deliveries could not get through. Damage was being assessed and details of insurance policies looked into. It was "too early" to count the cost of the riots, McMeikan said.

Sean Coughlan, director of the Croydon-based Coughlans/Munch chain said all 23 shops had been closed on police advice on Tuesday, with two outlets smashed up and looted on Monday night. The impact on trade would be "horrific", he said, adding: "I am very frustrated by the lack of government support."

Paul May CEO of 84-outlet Patisserie Holdings, which includes brands such as Druckers, said on Tuesday its outlet at the Bull Ring site in Birmingham had been hit and it was expecting poor sales overall. Also on Tuesday, Patisserie Valerie in Manchester had its windows smashed as trouble spread nationwide.

Tottenham craft wholesaler Flourish operations manager Shuk Ng said Flourish was at a standstill. She said: "We cannot get our vehicles through Tottenham for deliveries."

London Bread & Cake sales and development director Jack Humphries said: "These are tense times. We are busy, though people are turning to us to fulfill their orders as they cannot complete them."

Meanwhile, businesses damaged in the riots must act fast, warned law firm Reynolds Porter Chamberlain LLP. It said insurance firms can claim damages from the police for riots under the Riots (Damages) Act 1886, but claims must normally be lodged within 14 days of an incident.