It shall consult with the Competition Authority as appropriate. Article 17 Market analysis PTA shall, having regard to Article 16, analyse relevant markets taking into consideration obligations under the Agreement on a European Economic Area (EEA). Where appropriate, it shall co-operate with the Competition Authority in preparing such analysis. The analysing of markets shall provide a basis for decisions as to whether PTA shall place, maintain, amend or cancel obligations on undertakings with signi-ficant market power, as referred to in Article 18. Where competition is effective no obligations shall be placed on undertakings on these markets. If there is no effective competition in the market concerned, undertakings with significant market power in this market shall be designated as provided for in Article 18. They may be subjected to obligations as provided for in this Act, or such obligations which have already been imposed may be maintained or amended. Article 18 Significant market power An undertaking shall be deemed to have significant market power if it, either individually or jointly with others, holds a position of economic strength on a certain market which enables it to prevent effective competition and to operate to a sub-stantial extent without concern for competitors, customers and consumers. Where an undertaking either individually or jointly with others holds significant market power on a certain market it may also be deemed to have significant market power on a related market where the links between the two markets are such as to allow the market power held in one market to be used to strengthen market power on the other. The Minister of Communications may issue a Regulation on detailed market breakdown as referred to in Article 16, on definition of market situations, and on the yardsticks to be used in assessing whether undertakings, individually or jointly, hold significant market power as provided for in this Article. CHAPTER VI Universal service and specific electronic communications services Article 19 Right to universal service 10/34