The emergence of Tesco Compare.com have some calling for fair competition.

In what has become one of the worst kept secrets in the insurance industry, Tesco has finally launched its long awaited price comparison website.

Following months of speculation by the competition, Tesco unveiled its aggregator panel of 30 brands, backed by Royal Bank of Scotland and offering personal lines insurance, which will go live 14 September.

The news, feared by other aggregators, was that RBS-backed insurance brands including Churchill, Privilege, Nationwide, Lloyds TSB, Prudential and Virgin will only be available on Tesco Compare.com. RBS has eschewed aggregators in the past.

While many price comparison sites say they welcome the entry of Tesco into the market, claiming the recognised brand could attract more people to aggregator panels, the decision to leave RBS products off competitor sites has been highly criticized.

Confused.com’s managing director Debra Williams said: “It remains to be seen whether this is merely a commercial venture, designed to increase RBS’s market share by pitting itself against a selection of less competitive rivals, or whether Tesco is seriously committed to offering its customers a truly comprehensive comparison service. It is fantastic that RBS is finally changing its policy regarding services like ours, and we hope that it will now allow all of its insurance brands to be compared against the rest of the market by joining other comparison sites.”

uSwitch.com and Moneysupermarket.com have also joined the chorus of aggregators calling for RBS to allow fair competition to thrive within the market.

And for many, the irony of RBS – which owns long-time aggregator critic Direct Line – entering the price comparison market is not lost.

Although the war of words it waged for many months has recently calmed, Direct Line is adamant it will maintain its anti-aggregator stance.

But long-time price comparison sites argue, it’s hard to reconcile the fact that the parent company of one of the aggregator market’s staunchest critics has now entered the online market itself.

Perhaps this will add a new interesting element to the competition between these sites.

Previously the competition war was fuelled by mainly price alone but the existence of six exclusive brands on its site would seem to give Tesco Compare.com a distinct advantage.