"Asked whether emergency immigration controls were being considered , Mrs May said: "It is right that we do some contingency planning on this [and] that is work that is ongoing."
She said there was no evidence that migration was on the rise, but it was "difficult to say how it is going to develop in coming weeks".
BBC political correspondent Robin Brandt said the government had some room for manoeuvre because there are rules in place for extreme situations which allow for some temporary restrictions on immigration."
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