Leaked documents revealed that EU negotiators are preparing to open Brexit talks with an insistence that EU employment rights will continue in perpetuity for three million migrant workers already settled in the UK.
The move would guarantee pension rights and job security as well as maintaining controversial rules that mean foreign workers can claim child benefit for youngsters living overseas.
EU officials also want the European Court of Justice to oversee Britain’s compliance with the rules, effectively allowing Luxembourg judges to continue meddling in British affairs for decades to come.
Michel Barnier, the EU’s chief negotiator, wants the demand as part of a hard-line negotiating position once the Brexit talks open in earnest later this year.
In return, he will say the same rights will apply to British citizens living in EU countries after Brexit.
But a senior Tory source today insisted Mrs May will refuse the demands if she is returned to government after the general election on June 8.
The source said: “The Prime Minister has said Brexit is about taking back control of our money and our laws. This demand from the EU is not going to happen.”
Senior Tory MP Sir William Cash said it would be “completely impossible” for Mrs May to agree to the EU demand.
“The manner and depth of this authority would suggest that we are not leaving the EU at all.
“From the day we leave we cannot and will not be subject to the ECJ.”
According to a leaked European Commission document, European Court of Justice supervision “should be maintained” for all issues relating to “the continued application of EU law in Britain” after Brexit.
Another leaked Brussels document on the negotiations said: “Agreeing reciprocal guarantees to safeguard the status and rights derived from EU law at the date of withdrawal of EU and UK citizens, and their families, affected by the withdrawal of the UK from the union will be the first priority for the negotiations.”
A senior EU diplomat insisted that the European Court of Justice should retain authority over the UK for decades after Brexit.
“The withdrawal agreement with Britain will have followed Article 50 and is an act of the union.
“The ECJ is naturally the…