Operation Yellowhammer is the codename used by the UKTreasury for cross-government civil contingency planning for the possibility of a "no-deal" Brexit. In the event of no-deal, the UK's unilateral departure from the EU would disrupt, for an unknown duration, many aspects of the relationship between the UK and European Union, including financial transfers, movement of people, trade, customs and other regulations. Operation Yellowhammer is intended to mitigate, within the UK, the effects of this disruption, and would be expected to run for approximately three months. It has been developed by the Civil Contingencies Secretariat (CCS), a department of the Cabinet Office responsible for emergency planning.
The existence of the operation leaked on 6 September 2018, when a press photographer captured a snapshot of a document revealing some "no-deal" plans and the HM Treasury codename for them. The document appeared to indicate the CCS had been used in anticipation of government policy. No further details were revealed. The National Audit Office subsequently made public some documents about the operation.
The operation code name "Yellowhammer", which relates to a small songbird, was chosen at random.
Operation Yellowhammer covers actions to be taken in a no-deal scenario, some of which would be implemented prior to the date of leaving.
On 29 January 2019 the House of Commons voted, in a non-binding ballot, to reject a no-deal Brexit. However, unless the House of Commons were to accept the Brexit withdrawal agreement, or the EU's other members were to grant the UK an extension under Article 50 of the Lisbon Treaty, or the UK were to revoke its Article 50 notice, the United Kingdom would by default exit the EU on 29 March 2019 with no deal.
On 20 March 2019, Kent county council activated plans to keep roads, hospitals and schools open, and the UK government's Brexit secretary, Steve Barclay, said that Operation Yellowhammer command and control structures would be "enacted fully" on 25 March 2019 unless a new exit date was agreed between the UK and the EU. On 21 March 2019, the Ministry of Defence staffed a bunker under its Whitehall headquarters to coordinate no-deal related military activities under Operation Redfold, and the Cobra emergency committee took control of no-deal planning with intentions to implement national contingency plans on 25 March 2019.[Note 1]
Late on 21 March 2019, possible new exit dates were agreed between the UK and the EU:
22 May 2019 if the House of Commons approved the Brexit withdrawal agreement by 29 March 2019;[Note 2] or
The CCS may work with the Department for Exiting the European Union (DExEU) to achieve an objective for Brexit work, with the DDxEU concentracting on new policies, legislative changes and required funding changes with the CCS dealing with steps to mitigate and manage short term disruption. An example objective would be Continuity of supply of medicines into the UK after no deal exit from the EU falling within the areas of risk of key goods crossing borders and transport systems. Arrangements for prioritisation of key goods, additional ferry capacity and having procedures in place for operation customs operations that are effective immediately from the Brexit date are some of the areas covered.:15
Areas of risk
Operation Yellowhammer identifies 12 areas of risk. These include medicine supply chain and UK citizens in the EU. There are also three risks common to all areas.:7
In March 2019 the CCS had 56 people working internally on the programme; it is estimated 140 would be needed to maintain the operations centre and it has been budgeted to cost
£1.1 million in 2018–2019. This is in the context of the UK Treasury allocating £1.5 billion for Brexit preparations by government departments in 2018–2019.
3,500 troops are on standby to assist in the event of a no-deal exit, although the Ministry of Defence has only disclosed their mission will be to "support government planning".
On 21 March 2019, the UK government's decision to risk a no-deal Brexit and to invoke Operation Yellowhammer was criticised by the First Minister of Scotland, Nicola Sturgeon. Her sentiments were echoed by the First Minister of Wales, Mark Drakeford.
On 22 March confidential Cabinet documents on Operation Yellowhammer were obtained by The Guardian newspaper. The document warned that ministers could need to work 22.5-hour days, and departments would have to work 24 hours a day for at least twelve weeks without input from higher up in government. A source with knowledge of the operation said that, although planning had stepped up, the overall picture remained chaotic and "rudderless".
^"Meeting of the Parliament 21 March 2019 [Draft]". On operation yellowhammer, which is the emergency planning for a no-deal Brexit, it is beyond comprehension that any Prime Minister could knowingly allow the country to be eight days—about 200 hours—away from the possibility of crashing out of the European Union without a deal and to require that emergency planning work to be done.