The prime minister is to visit Berlin and Paris for Brexit talks as she seeks support for a further Article 50 extension.
Theresa May will meet with German chancellor Angela Merkel and French president Emmanuel Macron ahead of an EU summit on Wednesday.
All 27 remaining EU heads of government must agree to an extension if the UK is to avoid the default position of a no-deal Brexit on Friday night.
According to reports, Brexit could be delayed by nearly a year under plans being considered by EU officials.
Mrs May is expected to ask the EU for an extension to June 30 in order to get a deal past MPs.
On Monday night, the Commons backed a series of Lords amendments to the European Union (Withdrawal) (No 5) Act after it was rushed through both Houses of Parliament.
The cross-party move brought forward by Yvette Cooper and others led to Mrs May tabling a Commons motion for debate on Tuesday setting June 30 as the extension date.
The move came as the government and Labour were holding talks on trying to break the Brexit deadlock.
After officials from the two sides met on Monday, the fresh round of talks will include Mrs May's defacto deputy, cabinet office minister David Lidington, and Labour's shadow Brexit secretary Sir Keir Starmer.
Labour leader Jeremy Corbyn has called on the government to be more flexible regarding red line issues in the talks.