American Secretary of State John Kerry and Iranian Foreign Minister Mohammad Javad Zarif are the undisputed parents of the nuclear agreement reached on Sunday morning in Geneva, with certain bragging rights going to the diplomats who tended the secret and unofficial back-channel meetings that took place between the two countries in the months before the deal.

However, the outcome of the Geneva talks has brought into focus the midwifery skills of Baroness Catherine Ashton.

The much-derided European Union Foreign Policy High Representative shepherded not only this round of talks in Geneva but the countless rounds of negotiations between the Iranians and the P5+1 group of world powers over the past couple of years.

The judgment on her success in this role depends to a large degree on how one sees her position in the round.

Many in Britain perceive Mrs Ashton and her organisation as an unnecessary, overpaid, unqualified and unelected quango, a symbol of the EU’s overreach and meddlesome ways.

Even many Europhiles were extremely sceptical of a foreign policy chief with scant experience in diplomacy who speaks only English.

Now all sides have to admit that whatever they think of the agreement, it is highly doubtful that a deal would have been achieved without her repeated insistence on returning to the negotiating table, her ability to achieve a businesslike atmosphere around that table, and her apparent lack of personal ego.

“She has no political power and had to go back and ask six governments what they thought every step of the way,” said one diplomat involved in the talks, “but she kept everyone there.”

While some Israelis blame her for the recent guidelines on European investment across the Green Line and cannot forgive her for a rushed statement in which she seemed to be comparing the Jewish children killed in Toulouse last year and Palestinian children in Gaza, she has earned the respect of Israeli diplomats and politicians.

“I don’t believe she’s anti-Israel. Actually, she is very aware of Israeli concerns,” said one official who has met her a number of times. “She doesn’t decide policy. Her job is to push through the policy that others have formulated and she is surprisingly effective.”