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LONDON, Feb 21 (Reuters) - Britain wants to discuss with the European Union the length of any post-Brexit transition period, saying its government agrees it should be around two years but must be long enough to prepare "new processes" and "new systems".
Britain is due to leave the EU in March 2019. In a draft paper responding to the EU's legal text on its proposals for a subsequent transition period, British Prime Minister Theresa May's government said the timeframe "should be determined simply by how long it will take".
A government source said that did not mean Britain wanted to extend what May calls an 'implementation phase', but rather wanted to question the EU's position that any transition should end no later than Dec. 31, 2020.
Officials in Brussels have said they doubt whether Britain will be ready to make a full break by that date and are preparing for a much longer goodbye.
In the draft document, which was leaked to media, the government says: "The UK believes the period's duration should be determined simply by how long it will take to prepare and implement the new processes and new systems that will underpin the future partnership."
"The UK agrees this points to a period of around two years, but wishes to discuss with the EU the assessment that supports its proposed end date."
The EU and Britain were expected to agree to a largely status-quo transition, but Barnier said earlier this month that a deal was "not a given" after he accused London of bringing up "substantial" objections to the bloc's offer. (Reporting By Andrew MacAskill in London; additional reporting by Jan Strupczewski and Gabriela Baczynska in Brussels; Editing by Toby Chopra)