Supermarket giant Tesco is reported to have delayed launching an online rival to Amazon.

Testing has been taking place on the retailer's dedicated sales site – which at present is believed to share the Marketplace name with its main competitor – for three months.

Several retailers have already gone into partnership with Tesco to offer products on the site, including mother-and-baby store Mamas and Papas and electrical goods seller Maplin, Thisismoney.co.uk reports.

Speculation around the delay has focused on Tesco's search for a new advertising agency, but it announced a deal in this regard on Friday.

Tesco has come under fire for losing touch with its customers, having seen its profits fall this year as rivals such as Sainsbury and Morrisons continued to prosper.

It denied there were any issues delaying the launch of Marketplace, saying it has been concentration on "widening the product offering on Marketplace for customers and ensuring that everything is working smoothly".

Its non-food website, Tesco Direct, whose portal will be shared by the new site, was now selling 40 per cent more product lines, the company said in a statement.