Since his election Mr Chirac has failed to answer any German calls for more political integration, thereby weakening German support for the single currency, said Mrs Guigou, now a senior Socialist member of the European Parliament.
Questions over whether Germany will stick to the Maastricht commitment to move towards a single currency by 1999 have been raised by the German finance minister, Theo Waigel, as well as Hans Tietmeyer, president of the Bundesbank.
Helmut Kohl, the German Chancellor, whose commitment to the idea of European union has never been in doubt, has always insisted that monetary union must go hand in hand with greater political union. This is the price Bonn demands for the risks of taking a strong German mark into a monetary union with weaker European economies.
Many commentators in Brussels fear that the new German warnings on monetary union are directly related to the growing reluctance in Paris to deliver on political union. A breakdown in the Franco-German understanding, which was so strong between Mr Kohl and the last French president, Francois Mitterrand, may be at the root of the current instability.
Giving strong voice to these fears yesterday, Mrs Guigou said Mr Chirac had played into the hands of the French far right and refused to make any of the difficult choices which face Europe in the run-up to next year's Inter-Governmental Conference (IGC) on EU reform. In particular, Mr Chirac has refused to state his view on giving more power to the European Parliament, or on the greater use of majority voting in the Council of Ministers - both goals which Mr Kohl wants to achieve.
Germany, Mrs Guigou said, is "making a huge sacrifice" by entering monetary union. "It wants to know what Europe can give it in return for this sacrifice. So far it has not been told," she said. The meeting of EU leaders in Majorca at the weekend had produced only a "facade of consensus", said the MEP.
For John Major, the British Prime Minister, the slow-down by European leaders at Majorca was welcome. But in Brussels it has sparked extreme anxiety. Mrs Guigou said that with the IGC fast approaching, it was essential to do more than "paper over the cracks".
"Chirac has a horror of choosing. He must choose. What I fear is that he will choose too late," said Mrs Guigou.
Commenting on the new fears that monetary union could be delayed, Mrs Guigou said: "If it does not happen in 1999, there is little chance that it will happen at all. If that happens there will be no political union and Europe will become little more than a free-exchange zone."
Few diplomats or European Commission officials in Brussels believe it is possible for the political leaders to take formal action to delay the process towards monetary union, or to alter the criteria for joining as set down in the Maastricht treaty. A delay would necessitate a further inter-governmental conference, the result of which would have to be ratified by national parliaments. That would open up new and even more divisive debate. Such a public reversal of European policy would be devastating to the credibility of the entire union.
Mrs Guigou said yesterday that the onus now firmly lies with Mr Chirac to re-set France's course before the Madrid summit in December.