The development comes after European Union leaders signed off last week on the first stage of Brexit negotiations, ending more than a year of stalemate over Britain's bill for leaving the bloc, as well as the fate of the Irish border and European Union expatriates.
She wants to negotiate a transition deal with Brussels by March to reassure businesses and then seal a long term trade deal by October.
The European Union's chief Brexit negotiator said Wednesday that Britain should have less than two years as a transition period after it leaves the European Union and that the United Kingdom would have to live by all the key EU principles.
A Downing Street spokesman said she intends to have agreement in place over a transition period by March and then complete a deal on the future relationship with the European Union including trade.
"Encouraging EU banks to continue to operate in the United Kingdom will help preserve financial stability for the United Kingdom and the EU and will help defend London's position as an open global financial centre", said Miles Celic, head of the lobbying group TheCityUK.
He said that the deadline of December 31, 2020 was "logical" as it would avoid the complications derived from the United Kingdom still being subject to the bloc's rules and obligations once the EU's next multi-annual budget kicks in on January 1, 2021, Efe news reported.
European Union leaders last week agreed to open the second stage of Brexit talks, after approving an interim deal on Britain's financial settlement, expatriate rights and the Irish border.
Barnier appeared to throw the Brexiteers a bone on one of their key issues, however, saying that while Britain would be excluded from talks on fishing quotas during the transition, there would be "specific procedural arrangements" to give it a voice.
Europe has set a target date for when Brexit will really hit.
"But the real difficulties ahead lie when the British will ask for special system of regulatory alignment - they won't get it", he said.
May has already accepted in theory that the ECJ will continue to have jurisdiction and that London will have no legal basis to conclude its own trade deals during transition the period. It said in a statement, "The FCA welcomes the progress that has been made and is supportive of open markets and free trade in financial services underpinned by strong regulatory standards".
F1 sees distinguished manufacturers make a welcome return
It would also be nice to see a more competitive side to the sport, which usually sees one side dominate the entire season. The team is looking at Charles Leclerc from Ferrari, Marcus Ericsson or Antonio Giovinazzi who is a reserve for Ferrari.