As a member of the EU (which the UK remains, until the process for its withdrawal is complete), the UK is subject to EU public procurement rules (the Public Sector Directive 2014/24/EU and Utilities Sector Directive 2014/25/EU, together, the "EU Procurement Directives"). The EU Procurement Directives are implemented in the UK by the Public Contracts Regulations 2015 in England and Wales (the "PCR 2015") and the Public Contracts (Scotland) Regulations 2015 in Scotland, as well as the Utilities Contracts Regulation 2016 in England and Wales (the "UCR 2016" together with the PCR 2015, the "UK Regulations") and the Utilities Contracts (Scotland) Regulations 2016 in Scotland.

The Concession Contracts Directive 2014/23/EU was implemented in England, Wales and Northern Ireland by the Concession Contracts Regulations 2016 (the "CCR 2016") and in Scotland by the Concession Contracts (Scotland) Regulations 2016. Both sets of Regulations came into force on 18 April 2016 and govern the award of concession contracts. The CCR 2016 are addressed in further detail in the answer to question 2h below.

The implementing regulations in Scotland are similar to the UK Regulations, however, references made to the UK in this chapter will relate to the UK Regulations, which only cover England, Wales and Northern Ireland.

As noted above, the UK Regulations implement the EU Procurement Directives and will be invalid to the extent of any inconsistency with the EU Procurement Directives. As an EU member state, the UK is also a party to the World Trade Organisation's Agreement on Government Procurement (the "GPA"). The UK's exit from the EU is expected to occur at some point around or after March 2019. We do not yet know what effect this will have on the UK's public procurement regime or if the UK will enter into other agreements, such as the GPA, unilaterally.

The most fundamental principles underlying the legislation are those of transparency, non-discrimination and equal treatment, derived from EU procurement law. The EU principles of proportionality and mutual recognition are also relevant.

In accordance with the EU regime, defence procurement is governed by a different set of rules to the UK Regulations. The Defence and Security Public Contracts Regulations 2011 came into force on 21 August 2011, implementing the European Union Defence and Security Procurement Directive 2009/81/EC.