This thesis analyzes the withdrawal of the United Kingdom from the European Union and the impact of this process on air transport between the respecitve territories. The main goal of the paper was to determine the manner in which the issue of air freedoms, airline ownership and other factors that affect air transport were regulated after the completion of this process. The process of UK's exit from the EU ended with the adoption of the Agreement on Trade and Cooperation, which presents a comprehensive regulation of trade in goods and services between the two parties, of which air traffic regulation is a part. The Agreement restricted air freedoms by prescribing the existence of only four transport freedoms between the parties and has made the issue of ownership for UK airlines more stringent. In terms of commercial operations, the biggest changes have occurred in the allocation of slots, where the UK is no longer bound by the EU rules, as well as in the lease of aircraft, where the possibility of wet lease is limited. Analyzing the provisions of the Agreement, but also other regulation relevant for the relationship between the two sides, it was concluded that the UK's exit had a negative impact on its relationship withe the EU in air transport. The newly created regulation represents a step backwards in relation to the liberalized of the European Common Aviation Area, of which the UK was also once a party.