and in substitution for quotas and to such an extent as shall not impede the expansion  of the volume of trade provided for in Article 45( 2 ), a system of minimum prices  below which imports may be either:

temporarily suspended or reduced; or
allowed, but subjected to the condition that they are made at a price higher than  the minimum price for the product concerned.

In the latter case the minimum prices shall not include customs duties.

2. Minimum prices shall neither cause a reduction of the trade existing between  Member States when this Treaty enters into force nor form an obstacle to  progressive expansion of this trade. Minimum prices shall not be applied so as to  form an obstacle to the development of a natural preference between Member States.

3. As soon as this Treaty enters into force the Council shall, on a proposal from the  Commission, determine objective criteria for the establishment of minimum price  systems and for the fixing of such prices.

These criteria shall in particular take account of the average national production  costs in the Member State applying the minimum price, of the position of the various  undertakings concerned in relation to such average production costs, and of the need  to promote both the progressive improvement of agricultural practice and the  adjustments and specialization needed within the common market.

The Commission shall further propose a procedure for revising these criteria in  order to allow for and speed up technical progress and to approximate prices  progressively within the common market.

These criteria and the procedure for revising them shall be determined by the  Council acting unanimously within three years of the entry into force of this Treaty.

4. Until the decision of the Council takes effect, Member States may fix minimum  prices on condition that these are communicated beforehand to the Commission and  to the other Member States so that they may submit their comments.

Once the Council has taken its decision, Member States shall fix minimum prices on  the basis of the criteria determined as above.

The Council may, acting by a qualified majority on a proposal from the Commission,  rectify any decisions taken by Member States which do not conform to the criteria  defined above.

5. If it does not prove possible to determine the said objective criteria for certain  products by the beginning of the third stage, the Council may, acting by a qualified  majority on a proposal from the Commission, vary the minimum prices applied to  these products.

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