"We all deserve a clear promise before signing up - not a nasty surprise after," said Kroes, adding "when you buy a carton of milk, you don't expect it to be half-empty: the same goes for 50 Megabit internet."

The EU executive is expected to include the proposals as part of its digital telecoms package expected to be finalised in late July. A Commission source indicated that the basic outline of the deal would be agreed by commissioners next week.

In 2012, BEREC, the pan-European group of national Internet regulators, published a report claiming that between 20 and 50 percent of Internet providers in Europe use software to block or restrict access to websites and products run by rival companies. It estimated that around one in five fixed lines, and over one in three mobile users, suffered restricted services.

Internet campaign groups complain that the tactics used by internet service providers, who at the same time promote their own services, distort the online market and are an abuse of market position.

Bandwidth throttling, where a network provider deliberately slows down the Internet service on targeted websites, was identified as the most common restriction by BEREC.

Only two member states - the Netherlands and Slovenia - currently have national laws on net neutrality. Kroes added that consumers and new businesses were the big losers from the fragmented legal framework.

"They lack certainty about whether their new bright ideas will get a fair chance to compete in the market," she said.

For her part, Marietje Schaake, a Dutch Liberal MEP, urged the Commission to "end providers hampering the use of free services and their tracking of consumers' surfing behaviour."

"In the absence of regulation, internet providers could also block access to certain news or entertainment sites because of their financial interests. If access to competing news platform is hindered, this restricts people´s access to information," Schaake added.