UK accession to the 2007 Lugano Convention
On 8 April 2020, the United Kingdom deposited a request for re-accession to the 2007 Lugano Convention as an individual member.
According to Art. 72 of the Convention, the UK accession requires the unanimous consent of all contracting parties. While Switzerland, Norway and Iceland have already announced their support, the European Union and Denmark (which is an individual member due to its special status in EU civil justice cooperation) still have to give their explicit consent. The accession process may take up to one year, and its result is yet uncertain.
During the Brexit transition period (which is set to end on 31.12.2020), the 2007 Lugano Convention remains applicable in relation to the UK, although as an international convention signed by the EU, it would technically no longer be apply. In the Withdrawal Agreement, the UK and the EU agreed that Union law is defined as "including international agreements concluded by the EU" (Articles 129 and 2(a)(iv) of the Withdrawal Agreement). This arrangement was communicated to the non-EU Lugano States via the Annex to the Note Verbale on the Withdrawal Agreement. The latter have, however, not given a formal consent to this arrangement.
The future bares two risks for litigants: either the EU or Denmark do not consent to the UK's accession, or the Lugano accession process lasts until April 2021. The latter case would create temporary uncertainty for cross-border proceedings initiated after the end of the transition period. The former would lead to a more permanent gap in civil justice cooperation that can only partly be filled by the Hague 2005 Convention.
See also https://eapil.org/2020/04/25/uk-applies-for-accession-to-lugano-convention/
On the future of civil justice cooperation after Brexit see also www.biicl.org/publications/the-framework-of-judicial-cooperation-after-brexit-civil-and-commercial-matters.