Cyber Monday traffic is up 9% on last year but is unlikely to beat Black Friday when shoppers shunned the high street to spend £1.1 billion online, according to experts.

This year's Black Friday bonanza was the first time in the UK that online retail sales surpassed £1 billion in one day.

Experian-IMRG predicted £943 million will be spent online during Cyber Monday, 31% higher than the £720 million spent last year.

Rob Fenton, UK MD of business data agency fifty-five, said: "Cyber Monday struggles to attract such a devoted level of attention among British shoppers. Firstly, shopping fatigue sets in after Black Friday, as many consumers have already picked up all the bargains they need ahead of Christmas.

"Secondly, it is hamstrung by its own name - primarily making it an online only shopping day. This means retailers without a strong online presence, such as Primark, will pool all their deals and resources around Black Friday instead."

On Black Friday Amazon sold 86 items per second and enjoyed its biggest sales day ever in the UK, with more than 7.4 million items ordered.

The retail giant is introducing new deals every 10 minutes as part of its Cyber Monday offering which it has extended until Friday.

Black Friday was the Tesco Direct website's busiest ever 24 hours online and Currys PC World's website had over 6.5 million visitors between Friday and Sunday.

The large amount of traffic on Black Friday meant some websites struggled to cope and many of Britain's biggest retailers such as Argos and John Lewis left customers frustrated with slow page load times and multiple website crashes.

So far analyst PCA Predict has found Cyber Monday online traffic is 60% higher than on an average day in 2015.

The company said traffic between midnight and 8am was up by 9% compared to last year.

But some companies are also struggling to keep up with delivery demands, with one expert warning Cyber Monday orders will pile pressure on operators already battling to cope with the weekend's orders.

As many as one in ten of the 40 million items ordered on Black Friday and Cyber Monday could arrive late, according to estimates by supply chain experts LCP Consulting.

By the end of the day the Centre for Retail Research predicts spending online and in-stores across the entire Black Friday four-day period will hit £3.49 billion, with Mastercard going further and predicting UK consumers will end up spending £5.9bn on all retail sectors (excluding fuel).

Cyber Monday marks the end of a four-day pre-Christmas shopping splurge over the Thanksgiving holiday in the US but it has become a busy online shopping day in the UK thanks to discounting by retailers.

John Lewis has reported the biggest single-day's trade in its history after the company's Black Friday sales increased 11.9% on last year.

The UK retailer said Friday's sales peaked between 9-10am when the site was taking 4.9 orders per second.

The high street giant said increased footfall in shops also helped boost sales, with Saturday trading growing by 9.3% compared with last year.

Mark Lewis, the company's retail director, said: "Black Friday itself marked a record day for John Lewis and strong trade continued into the weekend.

"On Friday online trade really stepped forward, while shops saw their biggest increases over the weekend, showing that more than ever customers like to mix and match channels to shop in the most convenient way for them."

From Black Friday to Sunday the company's distribution teams processed 18% more parcels than last year, a rate which amounted to five units per second at its peak.