UPDATED 12.23PM The great Kiwi OE to the UK is under threat as the British Government discusses a crack-down on visas for students and skilled workers.

British Home Secretary Amber Rudd has told the annual Conservative Party Conference about proposed new visa rules to reduce numbers of people heading to the UK.

UK Correspondent Gavin Grey said Ms Rudd's worried that too many people are coming in to study at bogus colleges, with the sole purpose of staying on, so they want to make it harder on foreign students.

LISTEN ABOVE: UK correspondent Gavin Grey speaks with Larry Williams

He told Larry Williams they want fewer than 100,000 people entering the UK per year.

"[They're] going to have to cut back everywhere, because at the moment, it's 330,000 or so. So they've got to significantly cut it. Getting out of Brexit and preventing freedom of movement within the UK from Europe will go part of that way."

Grey said how that impacts Kiwi students remains to be seen.

"Yes, by cutting back that'll mean Europe will be cut back on the number of European ones. But what will that mean for those from Commonwealth countries? That's the slightly vague point at the moment."

ACT leader David Seymour said the traditional Kiwi OE can't be put at risk - he's suggesting a "free movement" agreement with Britain that could be extended to include Canada.

Mr Seymour said it's time for New Zealand to push for a two-way deal.

• UK flags tougher immigration rules for foreign workers

"Britain's revision of immigration settings is a chance to propose a free movement zone similar to what we have with Australia," he said.

"In the long term we could even negotiate a broader zone for citizens of Britain, New Zealand, Australia and Canada - CANZUK."

However, the British High Commission in New Zealand downplayed the effect of the proposed immigration changes on New Zealanders.

Spokesman Joel Watson said the changes were still in the consultation phase, and it was not yet clear what the impact would be.

But he emphasized that the Home Secretary’s speech made no reference to the UK’s Youth Mobility scheme, which is the route most Kiwis use for their OE.

“What it clearly doesn’t mean is that this is the end of the OE experience,” he said.

The Youth Mobility Scheme was currently under-subscribed. Around 4500 out of 12,000 places for New Zealanders were being taken.

“The UK has actually made it more straightforward for New Zealanders to visit the UK rather than harder,” Watson said.

“And that also includes increasing the number of spaces available under the OE.”

The restrictions on student migrants outlined by Rudd this week were targeted at lower-level courses, in particular English-language courses.

While no specific figures were available, New Zealanders were more likely to study higher degrees in the UK.

Watson also underlined the scale of the migration challenge that the UK was facing.

“The UK is growing at a rate equivalent to the city of Christchurch every five years. There’s a huge political imperative for the UK government to take action.”

Meanwhile, New Zealand First leader Winston Peters said New Zealand should follow the UK’s lead and crack down on immigration here.

Peters said Britain was aiming to reduce its 300,000 net intake to tens of thousands, while New Zealand had “done nothing to reduce record intakes of 70,000 net a year”.

Additional reporting by NZ Newswire and the NZ Herald