Britain wants data flows with the EU worth billions to continue unimpeded even after it leaves the bloc, the government said on Thursday.
"Data flows are important for the UK and the EU economies and for wider cooperation, including on law enforcement," the Department for Exiting the EU said in a position paper for negotiations on the issue.
"It is therefore essential that... we agree arrangements that allow for free flows of data to continue, based on mutual trust in each other's high data protection standards," it said.
The ministry emphasised that Britain would be starting from "an unprecedented point of alignment with the EU" on data protection when it leaves in March 2019 but did not say what would happen if data protection regulation in Britain or the EU changes.
The ministry said the EU's data economy was estimated to be worth 272 billion euros ($321 billion) in 2015, or around 2.0 percent of gross domestic product.
That figure is estimated to rise to 643 billion euros in 2020, or more than 3.0 percent of GDP by 2020.
According to ministry estimates, 75 percent of the flow of data out of Britain was to EU countries.
The third round of Brexit negotiations between Britain and the EU is due to begin next week.
The Confederation of British Industry (CBI), the main big business lobby, said the digital economy was "at risk of isolation" as a result of Brexit unless the government secures a transition deal.
TechUK, a trade body, has also argued that securing a future partnership agreement in data sharing would "take time" and previous deals have taken 18 months or more to negotiate.
Labour MP Chris Leslie, a leading supporter of the pro-EU Open Britain campaign, said the government's proposals were "likely to be impossible" as Britain is leaving the European single market.
"The government's position seems to be that everything should change and yet stay the same," he said.