LONDON (AFP) - While British politicians have spent the month since the EU referendum in a whirl of resignations, recriminations and political backstabbings, civil servants have been quietly beginning the mammoth task of implementing Brexit.
Unpicking 43 years of EU laws and regulations and forging new alliances outside the 28-nation bloc arguably represents the biggest challenge for Whitehall - as the civil service is collectively known - since World War II.
Prime Minister Theresa May has promised to implement the June 23 referendum vote to leave the EU - but what this means in practice is not yet clear.
In talks with German Chancellor Angela Merkel and French President Francois Hollande this week she said she would not launch the formal two-year exit process before the end of this year, to give the government time to formulate its position.
It will be up to the civil service to draw up options in terms of Britain's withdrawal from the EU, its future relationship with European allies and new trade deals.
Issues at stake range from the status of EU citizens in Britain and Britons living on the continent, to whether Britain will want continued access to the EU single market.
There are also questions over what happens to British recipients of key EU programmes such as agricultural subsidies and scientific research funding.
Three ministers will help shape Britain's new future outside the EU - Foreign Secretary Boris Johnson, Minister for Exiting the European Union David Davis and Minister for International Trade Liam Fox.
They all campaigned to leave the bloc in the referendum, but as individuals they have clashed in the past.
May, who campaigned to stay in the EU, will maintain control by personally chairing a Brexit cabinet group.
But leaving the EU will impact on almost everything in government, and May has told all her cabinet ministers that they have a responsibility to "make Brexit work".
The new Department for Exiting the European Union will oversee preparations on leaving the bloc and support the prime minister in negotiations for the divorce.
It will also lead work on establishing new ties with EU nations and consulting with those involved, from the devolved governments in Scotland, Wales and Northern Ireland to business and trade union leaders.
Oliver Robbins, a career civil servant with experience at the interior and finance ministries, was appointed to run the department in one of former prime minister David Cameron's final acts of office.
The department is currently based in the Cabinet Office at number nine Downing Street, next door to May's office, and has just 40 staff.
It intends to expand to about 200, taking some staff from the Foreign Office and Britain's current team in Brussels.
The new Department for International Trade, led by Fox, is charged with formulating a new trade policy outside the EU.
Informal talks have already begun with Canada and Australia, although Britain cannot sign any new deals until it formally relinquishes its EU membership.
Officials have said they are aiming for a withdrawal in early 2019.
A major problem is Britain's lack of trade negotiators.
Since 1972, it has relied on the EU to conduct all deals and has only 12 to 20 serving officials with any experience of trade negotiations, according to one former civil servant.
If it decides to leave the EU single market, Britain must negotiate a free trade agreement with the bloc as well as with non-EU nations.
The government aims to have up to 300 specialist trade staff by the end of the year.
All in all, Dominic Cook, associate fellow of the Said Business School in Oxford, estimates that up to 10,000 staff could be required to implement Brexit.
There are currently more than 1,000 British nationals working for the European Commission, and efforts will likely be made to try to lure some of them back.
But government will also likely need to turn to the private sector, with management consultancy firm McKinsey already working with the Brexit ministry.
"It's going to cost billions," Cook told The Times.