Theresa May has been accused of “losing momentum” and “making errors” by delaying the formal start of Brexit talks in the wake of Nicola Sturgeon’s shock demand for a Scottish independence referendum.
The Prime Minister was expected formally to start negotiations with other European Union member states as early as this week once Parliament had passed a law allowing talks to begin.
But The Telegraph understands that the Queen is likely to give the legal assent to the law that allows Mrs May to start Brexit talks on Thursday.
Mrs May is then understood to be targeting triggering Article 50 on Wednesday March 29, after a speaking tour of Britain when she will sell her vision for the UK outside the EU.
This delay has led to concerns that Mrs May now cannot begin formal talks until May, missing the chance of talks with EU leaders on April 6.
Lord Jones of Birmingham, a cross bench peer who was a trade minister in the last Labour government, said he “cannot understand why she has done it”.
The peer – who was head of the CBI for eight years – praised Mrs May for the way she has “handled” the period leading up to the start of negotiations.
But he told The Telegraph: “If she has delayed it by two weeks, I am disappointed, it is an error.”
The issue was not whether bilateral talks with Germany or other countries might not happen but more about the sense of stalling “momentum”.
Lord Jones said: “The issue is momentum. She is in mid-innings, she is dealing with the bowling. Don’t declare your innings now!”
Other MPs urged Mrs May to trigger Article 50 to avoid the chance of another legal challenge to the process being made to the process in the High Court.
Sir Bill Cash, the euro-sceptic Tory chairman of the EU scrutiny committee, said it is “essential that ministers take the best possible legal advice and act as quickly as possible. Getting the Article 50 letter out is an absolute priority.”
Former Ukip leader Nigel Farage added that he was worried the start of talks had been “kicked into the long grass in May”.
He said: ”Now that we are delaying the triggering of Article 50, what it means is that we will miss the summit of European leaders on April 6 at which Brexit could practicably have been discussed.”
Senior Government figures admitted that talks will not get under way properly in April because of the long Parliamentary recess and Easter meant there was “not much going on on the Continent”.
But the source denied that the delay would damage Britain’s interests because preliminary talks had been going on “for weeks” between the UK and European Union.
This is despite EU leaders insisting that Brexit talks cannot begin formally until Article 50 of the Lisbon Treaty has been formally triggered.
One said: “Despite the fact that they say there is no negotiating there is contact going on with the Commission.
“The officials have been in contact and met personally. It is underway, preparing the ground for negotiations, so we are not starting totally from cold when the notice has been served. The end of the month was what we were always aiming at.”
Gina Miller, the fund manager whose legal challenge forced the Government to legislate for the start of Brexit talks, threatened more legal action if MPs and peers were not given a proper vote on the final package.
She said: “If they don’t deliver on that I will take them back to court to find out whether they can do as they are intending to do.”
The Prime Minister's official spokesman played down suggestions she was delaying due to Ms Sturgeon's announcement, saying Mrs May had always said she would trigger Article 50 by the end of March.
The spokesman said: "I've said 'end' many times but it would seem I didn't put it in capital letters strongly enough."