European Council president Donald Tusk has suggested offering the UK a "flexible" extension to Brexit of up to a year, with the option of leaving earlier if a deal is ratified, ONA reports citing BBC.
He said there was "little reason to believe" a Brexit deal would be approved by the extension deadline UK PM Theresa May has requested - 30 June.
Writing to EU leaders, he said any delay should have conditions attached.
EU states will vote on the extension proposals at a summit on Wednesday.
A draft EU document circulated to diplomats ahead of the emergency summit also proposes an extension but leaves the date of the proposed new deadline blank.
The BBC's Brussels correspondent Adam Fleming said the document referred to an extension lasting "only as long as is necessary and, in any event, no longer than XX.XX.XXXX and ending earlier if the withdrawal agreement is ratified".
The UK is currently due to leave the EU at 23:00 BST on Friday.
Meanwhile, Mrs May has been meeting French President Emmanuel Macron in Paris and German Chancellor Angela Merkel in Berlin for talks ahead of the summit.
Afterwards, Ms Merkel said a delay that ran until the end of this year or the start of 2020 was a possibility.