The Brussels I Regulation and Brussels I Regulation (recast) will continue to apply for proceedings initiated before 1 January 2021.

For proceedings initiated as from 1 January 2021, international instruments will apply. The UK has made the necessary arrangements for the Hague Convention of 30 June 2005 on Choice of Court Agreements to apply as of the end of the transition period. The UK could also ratify the Lugano Convention on jurisdiction and the recognition and enforcement of judgments in civil and commercial matters, in the same way as the EU, Switzerland, Norway and Iceland. These instruments are, however, less effective than the current system in terms of streamlining cross-border procedures and ensuring legal certainty.

In the absence of applicable international instruments, each Member State’s domestic legislation will apply.

The Brussels II bis Regulation and European Regulation (EC) No 4/2009 will continue to apply for proceedings initiated before 1 January 2021. 

Other proceedings will be governed by the applicable international instruments. The UK is already party to a number of multilateral conventions that mirror EU legislation (Hague Convention of 1980 on the Civil Aspects of International Child Abduction and the Hague Convention of 1996 on the International Protection of Children). The UK has also signed the Hague Convention of 23 November 2007 on the International Recovery of Child Support and Other Forms of Family Maintenance. However, some matters are not covered by the Hague Conventions and domestic law will therefore have to be applied. For instance, this concerns the rules for court jurisdiction in divorce matters or maintenance obligations, or the recognition and enforcement of marriage-related decisions.

At the end of the transition period, domestic legislation will apply. However, for collective insolvency proceedings initiated before the end of the transition period, European regulations on jurisdiction, applicable law and the recognition of insolvency decisions will continue to apply.

At the end of the transition period, European regulations on the service of judicial and extrajudicial documents and the taking of evidence will no longer be able to be applied in legal proceedings if the request for mutual legal assistance is received  after 31 December 2020. These regulations will be replaced by the Hague Conventions which govern such requests but which do not allow direct cooperation in the same way as European instruments, and therefore lead to longer timeframes. 
European rules on legal aid will also be replaced by existing treaties (bilateral agreement and Hague Convention).

Decisions handed down in legal proceedings that were initiated prior to the end of the transition period will be enforceable in France under the EU law which governed them prior to withdrawal.

Decisions handed down in proceedings initiated after the end of the transition period will be enforced in France pursuant to the applicable international instruments, primarily the Hague Convention of 30 June 2005 on Choice of Court Agreements. In the absence of applicable instruments, decisions will be enforced pursuant to domestic legislation: a French court will have to grant exequatur, after checking that the decision was lawfully handed down and that it complies with international public policy.

The Paris Commercial Court and the Paris Court of Appeal have set up commercial divisions with judges who have a firm grasp of English and have perfect knowledge of English law. As a result, commercial litigation can be referred to them by requesting that they not only apply English law but also hold hearings in English, in the same manner as before English courts. The decisions handed down will be translated into English.

Legal proceedings or requests for cooperation which were initiated prior to the end of the transition period will be subject to the EU legislation which was applicable to them prior to the withdrawal.

Requests for cooperation received or decisions handed down in proceedings initiated after the end of the transition period will be enforced in France pursuant to the applicable international instruments.

Requests will have to be based, inter alia, on the Hague Convention of 25 October 1980 on the Civil Aspects of International Child Abduction, on the Hague Convention of 19 October 1996 on Jurisdiction, Applicable Law, Recognition, Enforcement and Co-operation in Respect of Parental Responsibility and Measures for the Protection of Children and, in respect of maintenance obligations, on the Hague Convention of 23  November 2007 on the International Recovery of Child Support and Other Forms of Family Maintenance.