(18)The Commission, in cooperation with ESMA, should continue monitoring on a regular basis the evolution and the effective implementation of the legal, supervisory and enforcement arrangements in the USA for OTC derivative contracts regarding the timely confirmation, portfolio compression and reconciliation, valuation, dispute resolution and margin requirements applicable to OTC derivative contracts not cleared by a CCP on the basis of which this Decision has been taken. This should be without prejudice to the possibility of the Commission to undertake a specific review at any time, where relevant developments make it necessary for the Commission to re-assess the equivalence granted by this Decision. Such re-assessment could lead to the repeal of this Decision.