Under the conditions laid down by national law, each Member State shall authorise reinsurance undertakings with head offices within its territory to transfer all or part of their portfolios of contracts, including those concluded either under the right of establishment or the freedom to provide services, to an accepting office established within the Community, if the competent authorities of the home Member State of the accepting office certify that, after taking the transfer into account, the latter possesses the necessary solvency margin referred to in Chapter 3.