The government could yet relocate the COP26 Climate Summit to London, according to reports this morning, amid claims of spiralling costs and political rows over the current Glasgow venue.

The Financial Times reported that officials from the Department for Business, Energy, and Industrial Strategy (BEIS) have opened talks with the ExCel London conference venue in East London, sparking speculation that the government could yet make a shock decision to relocate the high profile UN Summit.

An unnamed source played down the prospects of moving the venue, arguing that the London venue was being scoped out as a "fallback option".

"It's normal for an event of this magnitude to have contingency measures," they told the paper. "We are pretty committed to Scotland."

However, the reports will further fuel concerns about the government's preparations for the Summit, which is still lacking a President nearly two weeks after the sacking of Claire O'Neill.

Following her departure, the former Energy and Clean Growth Minister alleged the government was considering relocating the venue to England, warning that the budget for the Glasgow Summit was climbing fast and that preparations were massively behind schedule.

Downing Street denied at the time that there were any plans to move the Summit and observers maintain that a relocation remains unlikely.

But reports have suggested that Prime Minister Boris Johnson last year rejected the advice of officials in selecting Glasgow over London as the venue for the Summit.

COP Summits typically bring together upwards of 30,000 ministers, diplomats, officials, journalists, and campaigners from around the world, creating huge logistical and security challenges. This year's Summit is set to be larger and more logistically demanding than usual given it is expected to mark the official coming into force of the Paris Agreement and as such scores of world leaders are expected to attend, fuelling media interest and creating additional security requirements.

Insiders have indicated the costs of hosting the Summit in Glasgow are spiralling as the government works on plans to transfer hundreds of police from across the UK to the city.

Meanwhile, the UK and Scottish government are at loggerheads over venues, after the Scottish government reserved the Glasgow Science Centre, which is next to the events complex where the summit will be held. Scottish ministers maintain the UK government originally indicated it did not require the venue, but has now realised additional space is required for the official UN Summit and is calling on the Scottish government to relinquish the venue.

At the same time competition for hotel rooms and meeting spaces in the city is intensifying, as thousands of officials, journalists, and campaigners attempt to book up rooms for the fortnight duration of the Summit.

BusinessGreen understands some officials last year advocated for ExCel as the original venue for the Summit, noting that London's accommodation and policing capacity, the proximity to London City Airport, and the venue's experience hosting events such as the London Olympics and the 2008 international summit to tackle the financial crisis made it a suitable location.

But Number 10 is thought to have wanted to locate COP26 outside of London and saw Glasgow as a way to underscore its commitment to the Union.

That plan has been subsequently undermined by a series of public and attributed comments from Johnson criticising Scottish First Minister Nicola Sturgeon and suggesting that he wanted to minimise her involvement in the Summit.

Yesterday, both the Scottish and the Westminster governments sought to downplay the row and stress their commitment to delivering a successful Summit.

Speaking at a conference on the 'Countdown to COP26' hosted by think tank Green Alliance, Chancellor of the Duchy of Lancaster Michael Gove said the two governments were prepared to look past their political differences to deliver a successful Summit.

And later in the day Sturgeon struck a similarly conciliatory tone, calling for an end to the "squabbles" that have marred the preparations to date.

"I personally and my government are committed absolutely and unequivocally to working closely and constructively with the UK government, and with other partners, in preparing for COP26 - preparing logistically but also preparing logistically," she said at an event organised by Green Alliance on the Countdown to COP26. "It's vital that COP is a success. It's a massive opportunity. We have a duty to do everything we can to make it a success. That's certainly Scotland's interest, but it is in the interests of the UK as a whole - and most importantly of all it's in the interest of the planet."

The government is hoping to get preparations for the Summit back on track this week with a new COP26 President widely expected to be announced as part of the imminent Cabinet reshuffle.

Gove has been widely tipped for the job, but asked yesterday if he would like the role he struck an equivocal note, declaring that "I am very happy with the job that I have and I think there are many, many, many, many talented people who could do the job of COP President better than I could".

Speaking later in the day Nick Bridge, the UK's foreign secretary special representative for climate change, insisted that despite the absence of an official President a "huge amount" of work was being done behind the scenes to prepare for the Summit.

"Every ambassador and high commissioner is out there working out what that drum beat of action is and a lot of it is already happening," he said, adding that the UK's whole diplomatic mission had been "instructed to have [climate change] as their top international priority this year".

He also insisted "the resources are there", revealing that 50 new people had been recruited within the Foreign Office's climate diplomacy unit while the dedicated COP26 team is "approaching 200 people".