The EU is to set out contentious plans to clamp down on the "oligopoly" of the three main credit ratings agencies and encourage newer European rivals.

On Friday the author of the proposals, EU internal market commissioner Michel Barnier, fired a shot across the bows of the dominant US trio of agencies after the hugely embarrassing error committed by Standard & Poor's on Thursday, when it issued a downgrade of French sovereign debt by mistake.

Barnier, who will unveil his plans on Tuesday, said pointedly that they would create a European framework for civil liability "in the case of serious misconduct or gross negligence" indicating that this was especially relevant in the current case.

"This incident is serious and shows that in the current tense and volatile market situation, market players must exercise discipline and demonstrate a special sense of responsibility," he said. "This is all the more important since we are not talking about just any market player but one of the biggest rating agencies."

The EU has been gunning for the agencies – S&P, Moody's and Fitch since the financial crisis of 2008, with anger coming to a head last year when Greek debt was downgraded during tense negotiations on the country's first €110bn bailout.

The third assault on their pre-eminence in as many years will be three-pronged. First, customers will be forced to change agency every three years, or after 10 consecutive bond issues, and not return to the same one for four years.

Barnier has dropped plans for the EU to, in effect, create its own agency, but views mandatory rotation as a means of supporting the newer, smaller ones – such as Euler Hermes – while they establish their credibility.

However, under intensive lobbying from the industry, backed by the UK, he has agreed that, if a bond issuer uses two of the bigger agencies, they can retain one for more than three years.

Richard Hopkin, a managing director at the Association for Financial Markets in Europe, which represents bigger banks, said mandatory rotation could be counter-productive, increase volatility of ratings and decrease their quality.

Barnier's second weapon will be aimed at sovereign debt ratings, with agencies banned from issuing amended ratings "which do not accurately reflect the situation of the country concerned" and would "cause negative spillover effects to other countries" during crises.

The French commissioner has been keen to end what he calls "over-reliance" on ratings, and the third part of his initiative takes aim at the methodologies used by agencies, subjecting these to approval by the European Securities and Markets Authority. A clear objective is to encourage institutional investors to carry out their own credit risk assessments.

Last month Barnier said: "It is not the thermometer that causes the fever but the thermometer has to work properly to ensure you do not exaggerate the fever." He has now, however, allowed ratings agencies to create bigger thermometers through large-scale mergers. These were originally to be banned.