Opponents of plans to the EU patents directive won a major victory yesterday when the European Parliament demanded a restart to the decision-making process.

Leaders of the Parliament’s political groups unanimously backed a request that the European Commission repropose a draft directive on the patenting of inventions implemented by computer.

While the Commission could ignore the Parliament's request, it risks a major political battle with the assembly if it does so. In any case, the Parliament could reject any legislation it doesn't like at the end of the process.

If the Commission, which is responsible for preparing draft EU laws, decides to restart the legislative process, it will win time for opponents of the directive and give them more scope to try and prevent patent protection being extended to software.

Polish MEP and former prime minister Jerzy Buzek called the group leaders' move to request a restart of the legal process a "very good decision". He called for a real debate to start about the patents directive but stressed that the EU should set a limit of one year for agreeing to legislation on patents because Europe needs the rules to help foster innovation.

However, the decision was criticised by one of the main IT industry associations, EICTA. Mark McGann, EICTA’s director-general, said it was "unhelpful to see the legal uncertainty extended". The association represents major IT and telecom companies - who are the people most likely to benefit form the original legislation.

However, the initial reaction from the Commission did not suggest the Parliament would get its way easily. A spokesman for Internal Market Commissioner Charlie McCreevy said the Commission had "taken note" of the assembly's request while commenting that it appreciated efforts by the Luxembourg presidency to ensure the issue followed the usual decision-making procedures.

Alain Lipietz, MEP for the French Green Party, warned that ignoring the assembly's request would be regarded as an "insult" by the Parliament and would lead to them rejecting any version of the patent law that they do not agree with.

The announcement of the Parliament's decision coincided with a demonstration in Brussels by about 300 opponents of software. Protestors handed bananas to a representative of Luxembourg, which is currently chairing EU meetings, to highlight their call to stop the European Union becoming a "banana republic" by ignoring the level of opposition to the planned directive.

The fight over the software patents directive has become one of the most bitterly contested pieces of legislation in the EU's history.

Originally designed to extend patent protection to inventions that are implemented by computers, such as mobile phones or washing machines, the legislation has been attacked as opening the door to a US-style patent regime where "pure" software and business methodology, such as Amazon's One Click online purchasing process, can be protected against imitation.