The Withdrawal Agreement also includes a protocol on Ireland and Northern Ireland, which provides for a “backstop” that the UK holds in a “single customs territory” with the EU at the end of the transition period, unless or until the entry into force of a new agreement on a future relationship between the UK and the EU ensuring the absence of border controls between Northern Ireland and Ireland. This is based in part on the Temporary Customs Arrangement between the UK and the EU proposed by the government in a June 2018 technical note. The June proposal suggested that further technical discussions with the EU would be needed to find a common solution to ensure that the UK is able to fully apply the EU`s common external tariffs and that the UK continues to benefit from existing EU free trade agreements or new agreements signed during the period. On January 20, 2019, Liam Fox said he was confident that Britain could repeat the five most important trade agreements by March 29. He said that there are 34 free trade agreements that need to be replicated. However, he said a number of countries were “not ready to prepare for a no deal”. Each trade agreement aims to reduce tariffs and remove other barriers to trade that come into force. It will also aim to cover both goods and services. In addition to these agreements, the list of signed agreements published by the Brexit Minister on 25 January 2019 referred to insurance agreements with the United States and Switzerland as well as a road transport agreement with Switzerland. Various multilateral agreements for which the United Kingdom is taking steps to become an independent party have also been listed.

These include international civil law conventions, various fisheries agreements and agreements, the Common Transit Agreement, the Interbus Agreement and the WTO Agreement on Government Procurement (GPA). This has been agreed in principle, with some outstanding technical issues to be concluded in 2019. As a member of the EU, the UK currently participates in many international agreements with third countries. The EU database Europa online treaties lists 1,261 international agreements to which the EU is a party. The government introduced the Trade Act in November 2017 to enable the domestic implementation of these alternative agreements and also to implement other measures necessary for an independent trade policy of the UK after Brexit. .