Theresa May has written to the European Union to request a further delay to Brexit until 30 June.
The UK is currently due to leave the EU on 12 April and, as yet, no withdrawal deal has been approved by MPs.
The prime minister has proposed that if UK MPs approve a deal in time, the UK should be able to leave before European Parliamentary elections on 23 May.
But she said the UK would prepare to field candidates in those elections in case no agreement is reached.
It is up to the EU whether to grant an extension to the Article 50 process, under which the UK leaves the EU, after MPs repeatedly rejected the withdrawal agreement reached between the UK and the bloc.
BBC Europe editor Katya Adler has been told by a senior EU source that European Council President Donald Tusk will propose a 12-month “flexible” extension to Brexit, with the option of cutting it short, if the UK Parliament ratifies a deal.
But any proposal would have to be agreed unanimously by EU leaders when they meet on 10 April .
Nearest tube: Elephant & Castle underground station (Northern and Bakerloo lines).
Nearest Railway Station: Elephant & Castle
Buses from Elephant and Castle: ask bus driver for Burgess Park. Bus numbers: 12, 171, 148, 176, 68, 484, 42, 40, 45