Britain will do its utmost to negotiate a divorce deal with the European Union that is mutually beneficial, Brexit minister David Davis says, setting out the government’s strategy in an official policy document.

The publication of the “White Paper” on Thursday is part of an attempt by Prime Minister Theresa May to keep lawmakers on side as she launches Britain’s formal divorce talks with the EU.

Britain’s future relationship with the European Union has split opinion in parliament, where the majority of lawmakers voted to remain a member of the bloc in a June referendum. Some fear May is leading the country towards a chaotic Brexit, with no framework for future economic and security cooperation.

Introducing the document, Davis defended the government against charges it had offered lawmakers no time to consider its Brexit White Paper which, some said, gave little detail beyond what May has already said.

“We will seek a new strategic partnership. A bold and ambitious free trade and customs agreement that should ensure the most free and frictionless trade in goods and services that is possible,” Davis told parliament.

“That will be to our mutual benefit.”

He reiterated May’s priorities in the negotiations, which she wants to launch before the end of March, and the paper offered some detail on how the British government saw the divorce process, suggesting a phased implementation.

But several opposition lawmakers said the government was still keeping parliament in the dark over its plan to leave the EU, a criticism which has been repeated against May who has said she does not want to give away her negotiating hand.

“For months we’ve been calling for a plan … now there’s a White Paper too late in the day to ask meaningful questions … That is completely unacceptable,” said Keir Starmer, Brexit spokesman for the opposition Labour Party.

The white paper on Brexit: a wish list disguised as a strategy https://t.co/l2dDyt4713

— The Guardian (@guardian) February 2, 2017

Under pressure to give the parliament more say over her plans, May was forced by a Supreme Court ruling to draft a new law giving her the right to trigger Article 50 of the EU’s Lisbon Treaty and start the talks.

With a majority in parliament, she cleared the first legislative hurdle for the bill on Wednesday but the new law will face more scrutiny by lawmakers next week.

Brexit White Paper: No detail, no data, no risk analysis, no financial impact assessment, no timing, no costs. Might as well be white paper.

— Alex Andreou (@sturdyAlex) February 2, 2017