Industry lobbyists fear the rise of protest parties and anti-EU rebels in European elections threatens to leave them, and the businesses they represent, out in the cold.

Europeans frustrated by economic hardship are likely to vote to give one in four of the European Parliament’s 751 seats to eurosceptics and protest parties of both left and right.

"There are going to be very vocal personalities ranting against the EU," said Derk Jan Eppinck, a Dutch member of the current parliament that draws its members from 28 European countries from Sweden to Romania. "These groups are anti-globalisation. It's contagious. This will be implanted in parliament. The end effect of this is anti-business," he said.

Although around 70 per cent of parliament's seats are expected to go to four mainstream groups - the centre-right European People's Party, centre-left Social Democrats, Liberals and Greens - protest groups could gain a decisive edge.

A far-left group could gain critical mass, possibly winning positions on the more than 20 committees that forge the parliament’s position on legislation or trade.

To compound the problem, many of these new members will take their place at the expense of centre-right and liberal pro-business lawmakers. Costas Chrysogonos, a candidate for Greece's leftist party Syriza who is campaigning against what he describes as "economic genocide" enforced by international lenders on his country, is typical of the new generation. "The European Union is being transformed into a new kind of Europe for the capital markets," he said. "My priority is not money. It's not capital. My priority would be the people." For industry, the arrival of this type of lawmaker in Brussels marks a worrying trend.

"They put their national flags on the table and shout," said Christian Feustel of Business Europe, a group that represents industry in Brussels. "They're not open to any arguments because they are ideological. We are not going to knock on their door. They don't understand business and they're not interested."

The advance of the protest parties in next week's elections poses a problem for more than 15,000 lobbyists who try to influence EU decision-making. While the European Commission drafts law for the region and countries must sign off on it, lawmakers in the parliament often have an equal say.

Simon Hix, co-founder of VoteWatch Europe, which analyses voting patterns, predicts that the eurosceptic right alone will win roughly 120 members of the parliament, with a further roughly 15 on the far right.

Among eurosceptics are lawmakers led by French National Front leader Marine Le Pen and the Netherlands' right-wing politician Geert Wilders. A separate Europe of Freedom & Democracy group may be dominated by the United Kingdom Independence Party (UKIP). Left-wing radicals will also take further seats. Many of these lawmakers will prove hard for lobbyists to visit. "Their attendance in parliament is probably going to be quite low," said Hix. "They don't turn up because they feel there is no point."

Lobbyists fear that those who do come to Brussels will not want to talk, for fear of being criticised for having close relations with business. "Europe will have its own Tea Party - socially conservative and against the 'federal' model, with members who are opposed to the whole idea of the EU," said Andras Baneth, who advises U.S. companies on lobbying in Brussels. "They are opposed to corporates' right to lobby."

The anti-EU drift will weaken the now powerful centre right, the parliament's single largest group, forcing it to broker deals with Social Democrats and making it harder to pass laws. "There will be a need to cooperate with the socialists to get a majority," said Andreas Schwab, a German lawmaker who coordinates voting among centre-right peers. "The risk is that certain legislation won't pass." More than anti-capitalism, it is the protest groups' political agenda to break up the European Union that will prevent them from bonding with industry voices. In Britain, UKIP is expected to top the polls in next week's vote. "There is a sense among British business that the country's influence in Europe has decreased, which is partly down to disengagement with Brussels," said Adam Marshall of the business lobby group British Chambers of Commerce.

"This is making it harder to argue our case." The growing popularity of lawmakers looking to quit the European Union means this is unlikely to change. "We will of course interact with the business community," Nigel Farage, the leader of UKIP, said. "But our objective is to leave." "Our objective is not to be subject to their (EU) laws. We want to make our own laws."