Ségolène Royal, France’s environment minister, has criticised the sluggish pace of UN climate negotiations, saying they are so unwieldy they threaten efforts to seal a global warming deal in Paris this year.

“The procedure isn’t really suited to what we need for climate change,” Ms Royal told reporters in London on Thursday, saying negotiators had made little progress on the main text of the Paris agreement, despite working on it for months.

“If you tried to run a business like that it would have gone bust long ago,” said Ms Royal, a former candidate for the French presidency. “The main obstacle [to the Paris agreement] is the procedure.”

Negotiators from almost 200 countries have been working on the draft text since last December, when a preliminary document running to nearly 40 pages was agreed at a two-week meeting in Peru.

The draft grew to more than 80 pages at a week-long meeting in Geneva in February, after countries were invited to add more options and proposals for curbing the greenhouse gas emissions driving climate change.

Negotiators will gather in Bonn, Germany, next Monday to begin another two-week conference. One of the main aims will be to whittle down the repetitive, jargon-ridden text to a more manageable size. Two further meetings are scheduled before the final two-week summit starts in Paris on November 30.

Ms Royal, whose government is eager to avoid repeating the failure of the last big attempt to seal a global climate deal — in Copenhagen in 2009 — said a different process was needed.

“You need to have people around the table day after day,” she said, adding that they should “make sure that what was agreed the day before continues to be agreed the day after”.

Few observers of the UN climate talks, which have been held in their current form for almost 20 years, expect a key breakthrough in Bonn.

Jonathan Grant, director of sustainability and climate change at the professional services group PwC, said: “Real progress is unlikely as countries will not compromise much at this point.”

He noted that the French government and the Bonn-based UN secretariat that oversees the cumbersome talks had been working to address the failures of past negotiations, when many countries objected to “a perceived lack of inclusiveness and transparency”.

One big difference between Copenhagen and Paris is that countries are already publishing their respective plans to cut emissions, well ahead of the final meeting where the deal is to be signed. The US, EU, Russia and Canada are among leading emitters to have done so, with others expected to follow in the coming months.

Many scientists say, however, that what they are promising to do will collectively fail to add up to sufficient action to limit global warming to no more than 2 degrees Celsius (from pre-industrial times). This is a threshold countries have already said should not be breached if risky climate change is to be avoided.

This makes it is imperative that the Paris agreement includes a system for countries to ratchet up their emissions cuts in future, said Liz Gallagher, a climate analyst at E3G, an environmental advisory group. “That’s the area that needs the most work” in Bonn, she said.

Yvo de Boer, a former head of the UN climate secretariat, said Bonn would be a key test for determining whether negotiators could produce the core elements needed for a meaningful Paris deal.

“There’s very little time left. You have an enormous number of countries at the table with an enormous number of proposals to be considered and almost no time to consider them,” he said.

“Bonn and the subsequent process will need to be extremely businesslike and focused if something clear is going to come out of Paris.”