Theresa May has said the UK "cannot possibly" remain within the European single market, as staying in it would mean "not leaving the EU at all".
But the prime minister promised to push for the "greatest possible" access to the single market following Brexit.
In a long-awaited speech, she also announced Parliament would get a vote on the final deal agreed between the UK and the European Union.
And Mrs May promised an end to "vast contributions" to the European Union.
The prime minister used the speech to announce the 12 objectives the UK has set for its negotiations with the EU, including:
- Maintaining the "common travel area" between the UK and Irish Republic
- Tariff-free trade with the EU
- A customs agreement with the EU
- Continued "practical" sharing of intelligence and policing information
- "Control" of immigration rights for EU citizens in the UK and UK citizens in the EU
Mrs May said there would not be a "blow-by-blow" account of negotiations, set to get under way after Article 50 of the Lisbon Treaty is invoked by the end of March. It was not her intention to "undermine" the EU or the single market, she added.
But she warned the EU against a "punitive" reaction to Brexit, as it would mean "calamitous self-harm for the countries of Europe and it would not be the act of a friend".
She said: "This agreement should allow for the freest possible trade in goods and services between Britain and the EU's member states.
"It should give British companies the maximum possible freedom to trade with and operate within European markets and let European businesses do the same in Britain. But I want to be clear: what I am proposing cannot mean membership of the single market."
