Australia has not yet been welcomed into a new “high ambition coalition” of 100 nations at major climate talks in Paris, despite claiming it had joined through the European Union.

Marshall Islands Foreign Minister Tony de Brum revealed the alliance of around 100 countries, including the United States, this week at the United Nations summit.

Australia was not among them and Foreign Minister Julie Bishop seemed unaware of the group when it was revealed on Wednesday.

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Mr de Brum, who spearheaded the alliance, issued an open invitation to countries in Paris.

A spokeswoman for Ms Bishop on Friday confirmed Australia had been formally invited by the European Union and had accepted the invitation.

However, it appears Australia hasn’t yet been welcomed into the group, the Marshall Islands hinting the country would have to prove its worth.

“We are delighted to learn of Australia’s interest and look forward to hearing what more they may be able to do to join our coalition of high ambition here in Paris,” a spokesman for Mr de Brum said.

Earlier on Friday Mr de Brum read out a list of countries that had accepted his open invitation, with Australia notably absent.

Canada which, like Australia, has been criticised for a lack of climate action in recent years, joined on Thursday.

Both countries have recently installed new prime ministers.

Ms Bishop later said there had been some confusion among proponents of the alliance.

“It’s just a group of like-minded people who want to see an ambitious agreement,” she told reporters in Paris.

“We are part of this coalition, but it’s just people signing up saying, ‘We want to see an ambitious agreement’.”

She had spoken to Mr de Brum and he was happy with Australia’s decision to accept the EU invitation.

The group is calling for a strong climate agreement and bridges the historical divide between rich and poor and large and small countries.

The spokesman said it involved 25 ministers who negotiated on behalf of 97 countries.

“The list is constantly expanding as more ministers reach out directly to Minister de Brum and affirm their personal commitment to achieving the strongest possible deal here in Paris.”

The Marshall Islands said the alliance’s four major demands were a single package and would not be traded off for one another.

In the latest iteration of the text many of their demands were met, including an aspirational goal to limit global warming below the previously agreed 2C.

It’s hoped the historic climate agreement will be forged during the weekend.

WHAT THEY WANT *Reference to limiting global warming to 1.5C (is in the text)

*Clear path towards a low-carbon future (emissions neutrality by second half of century in text)

*Five yearly updates (is in the text)

*Strong package of financial support for developing nations ($100 billion per year plus scale up after 2020 is an option in the text – could be removed)