THE former president of the UN's COP26 climate summit in Glasgow, who was sacked by the UK Government last week, has launched a scathing attack on the Prime Minister's environmental record.

In her letter to Boris Johnson, Claire Perry O'Neill suggested his personal animosity towards First Minister Nicola Sturgeon is endangering the success of the summit.

The former clean growth minister also claimed the Prime Minister is considering relocating the event to an "English location" because of "ballooning costs".

O'Neill spoke out as Johnson outlined some new climate measures, including a ban on sales of new petrol and diesel vehicles from 2035.

The Financial Times published a letter written by O'Neill to Johnson in which she said promises are "not close to being met".

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She wrote: "You promised to 'lead from the front' and asked me what was needed: 'Money, people, just tell us!' Sadly these promises are not close to being met."

She added: "This isn't a pretty place to be and we owe the world a lot better."

O'Neill said Johnson had not convened the Cabinet sub-committee on climate change as promised and added his government is "miles off track" in setting a positive agenda ahead of the November summit.

She went on: "I am told by COP unit sources that budgets (which I do not see) are ballooning, the team and the Scottish Government are in an extraordinary state of stand-off and that you are considering re-locating the event to an English location.

"I had asked if you would consider re-setting your relationship with the First Minister - putting aside the devolution battle for the sake of this vastly important agenda. I understand you declined in salty terms."

Last year the COP26 made headlines as it emerged that while speaking at the Conservative confernece, Johnson had suggested he would not want Nicola Sturgeon at the summit.

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The talks this autumn will be the most important since the Paris Agreement to curb global warming was secured in 2015.

At the summit, countries are expected to deliver more ambitious domestic plans for cutting greenhouse gases by 2030.

O'Neill, who stood down as a Tory MP at the General Election, was sacked as president of the talks by the PM's special adviser, Dominic Cummings, on Friday, with the Government saying the post would be a ministerial role in future.

But Nick Mabey, chief executive of climate change think-tank E3G, said the UK's presidency had got off to a bumpy start with the decision to dismiss her.

Her replacement has a "daunting task" and will need to be a political heavy hitter, with an immense diplomatic effort needed from the UK to steer the negotiations, he said.

O'Neill is also reportedly consulting lawyers about what she claims were "false, distorted and defamatory" briefings about her record, saying Number 10 was "rumoured" to be behind the briefings.

She told the Financial Times she had been considered for a peerage by Downing Street to give her more authority in her UN summit role, but this had now been "firmly rescinded".