LONDON >> A committee of British lawmakers is urging Prime Minister Theresa May to clarify her intentions on Brexit — particularly whether she intends to keep Britain in the European Union’s large single market.

The House of Commons’ Exiting the EU committee urged May to publish her plan soon and to give lawmakers a vote on whatever deal is concluded with the 28-nation EU. Their report was released Saturday, just days before May is to deliver her vision about Britain’s post-EU future in a major speech.

“This is going to be a hugely complex task and the outcome will affect us all,” committee chair Hilary Benn said. “The government needs to publish its Brexit plan by mid-February at the latest, including its position on membership of the single market and the customs union, so that it can be scrutinized by Parliament and the public.”

Members of the committee also warned that the task of preparing for Brexit was placing a “strain” on departments across the British government and said more staff may be required.

The committee is seeking a framework of the U.K.’s future trading relationship with the EU as part of the Article 50 negotiations — arguing that transitional arrangements would be needed for trade to continue if a deal wasn’t complete by 2019.

It acknowledged, though, that Britain’s government may not be in a position to deliver this objective, since it would also depend on the other 27 members of the EU.

“The U.K.’s relationship with the EU is deep and complex, not least in terms of the legal rights of parties in both the U.K. and the EU-27,” the report said. “It would be unsatisfactory and potentially damaging to both sides were the U.K. to leave the EU with no agreement having been reached.”

The committee said it was important that financial service providers have confidence in the new arrangements and that the government should seek to ensure continued access to EU markets by way continuing passporting rights.

The principle of “passporting” allows any firm registered in one EU country to operate in any other member state without facing another layer of regulation. It allows EU exporters to ship their goods to any EU country free of tariffs.

Losing that freedom is a particular concern for the many foreign firms in London who use the British capital not only as a financial hub but as an entry point into the EU.