Amazon was hit by strikes at various locations in Britain, Germany and Italy during the annual "Black Friday" shopping extravaganza as workers demand higher wages and better working conditions.

UNI Global Union said Amazon would face strikes and protests in more than 30 countries around the world, including the United States, as part of a "Make Amazon Pay" campaign.

"Workers know that it doesn't matter what country you're in or what your job title is. We are all united in the fight for higher wages, an end to unreasonable quotas and a voice on the job," said Christy Hoffman, general secretary of UNI Global Union.

"That's what workers in Coventry are striking for and that is why workers around the world are standing up to Make Amazon Pay," Hoffman said.

Held the day after the US Thanksgiving holiday, "Black Friday" is increasingly copied in Europe and beyond, with stores offering big discounts to kick off shopping for the holiday gift-giving season.

More than 1,000 workers went on strike at an Amazon hub in Coventry, England, which employs 2,300 people and supplies other warehouses, said Stuart Richards, spokesman for the GMB union.

In Germany, the industrial action called by Union Verdi began in the night to Friday, affecting five out of the US e-commerce giant's 20 logistic sites in Europe's biggest economy.

Amazon said the strikes in the UK and Germany would have no impact on customers.

Workers at the Amazon hub in Piacenza, near Milan, joined the strike, with a "very high participation" rate, said Roberto Brambilla of the Filcams Cgil union.

"The mood music is souring for Amazon over this important time as industrial action over pay and conditions by warehouse staff could threaten performance," said Sophie Lund-Yates, lead equity analyst at Hargreaves Lansdown.

This "will be something monitored closely by investors," she added.

'Turning point'

In Britain, the GMB union said Amazon has refused to talk to workers.

"The pressure GMB members have put on the company has led to Amazon offering pay rises across the board but what they offer is still a long way short of what workers want," Richards said.

Workers want their pay to rise from £12 ($15) per hour currently to £15 per hour.

An Amazon UK spokesman said the company regularly reviews its pay "to ensure we offer competitive wages and benefits".

He said starting pay in the UK will rise to between £12.30 and £13 per hour depending on the location, from April — a 20-percent increase over two years and 50 percent since 2018.

In Germany, Amazon said workers already had a "fair wage and good additional benefits".

Starting wages are at 14 euros ($15.30) and above per hour, the company said, higher than Germany's minimum wage of 12 euros. 

But Verdi is pushing for the company to recognise the regional collective agreements of the retail and mail order sector.

In Italy, the union complained about "unacceptable" pay increases as well as a failure by Amazon to raise the amount of meal vouchers and a lack of attention to health issues, among other reasons.

"Today will go down as a turning point in Amazon's history," said GMB official Amanda Gearing.

"With industrial action escalating and workers joining strike action in Europe and the USA, it's clear this strike is inspiring Amazon workers worldwide to fight to force the company to change its ways," Gearing said.