In a tense exchange with Labour's Yvette Cooper, the Prime Minister repeatedly refused to say when she would set out new migration controls to be placed on EU citizens after the UK leaves the bloc.
Asked at a session of the Liaison Committee whether Ms May will set out controls as part of a plan she has pledged to publish in the run up to triggering Article 50, the Prime Minister said: "We are working on our proposals for immigration, there are a number of ways in which we can address the issue.
"When we feel it is appropriate to give any indications of those details then we will do so."
The Prime Minister repeated the answer when asked by Ms Cooper, who also chairs the Home Affairs Committee, if that means details of new controls may not come as part of Ms May's plan.
Ms May then did not challenge Ms Cooper when she said she would assume, in that case, that details of migration controls would not be published with the plan.
Net migration into the UK is currently running above 300,000, with much of the figure coming from the European Union. Ms May has maintained the promise to bring the overall number down to the 'tens of thousands'.
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