1.   When calculating, in accordance with Article 233, the group solvency of an insurance or reinsurance undertaking which is a participating undertaking in a third-country insurance or reinsurance undertaking, the latter shall, solely for the purposes of that calculation, be treated as a related insurance or reinsurance undertaking.

However, where the third country in which that undertaking has its head office makes it subject to authorisation and imposes on it a solvency regime at least equivalent to that laid down in Title I, Chapter VI, Member States may provide that the calculation take into account, as regards that undertaking, the Solvency Capital Requirement and the own funds eligible to satisfy that requirement as laid down by the third country concerned.

2.   The verification of whether the third-country regime is at least equivalent shall be carried out by the group supervisor, at the request of the participating undertaking or on its own initiative.

In so doing, the group supervisor shall consult the other supervisory authorities concerned and CEIOPS before taking a decision on equivalence.

3.   The Commission may adopt implementing measures specifying the criteria to assess whether the solvency regime in a third country is equivalent to that laid down in Title I, Chapter VI.

Those measures, designed to amend non-essential elements of this Directive by supplementing it, shall be adopted in accordance with the regulatory procedure with scrutiny referred to in Article 301(3).

4.   The Commission may adopt, after consultation of the European Insurance and Occupational Pensions Committee and in accordance with the regulatory procedure referred to in Article 301(2), and taking into account the criteria adopted in accordance with paragraph 3 of this Article, a decision as to whether the solvency regime in a third country is equivalent to that laid down in Title I, Chapter VI.

Those decisions shall be regularly reviewed to take into account any changes to the solvency regime laid down in Title I, Chapter VI, and to the solvency regime in the third country.

5.   Wherein accordance with paragraph 4 the Commission adopts a decision on equivalence of the solvency regime in a third country, paragraph 2 shall not apply.

Where a decision adopted by the Commission in accordance with paragraph 4 concludes that the solvency regime in a third country is not equivalent, the option referred to in the second subparagraph of paragraph 1 to take into account the Solvency Capital Requirement and eligible own funds as laid down by the third country concerned shall not be applicable and the third-country insurance or reinsurance undertaking shall be treated exclusively in accordance with the first subparagraph of paragraph 1.