The Alpine country has begun implementing austerity measures in a bid to reign in Austria's ballooning budget deficit, which breaches European Union limits.

"The particularly high costs due to logistical reasons for the Federal President's participation in this year's COP, in addition to the Austrian negotiating delegation, are not within the tight budgetary framework," said a statement sent to AFP.

Austria's "budget consolidation... requires all public authorities to make cuts and exercise... discipline," Van der Bellen said in the statement.

The decision to skip the summit had not been taken lightly, he added.

Wishing Brazil "all the best for a successful COP", Van der Bellen said Austria's negotiating delegation would still take part.

Several COP30 countries and campaign groups have already expressed concern about the shortage of accomodation and exorbitant prices hotels and property owners are charging in Brazil's Amazonian city of Belem.

Brazil recently ruled out changing the venue after complaints about sky-high room prices in the far-flung destination, vowing to tackle the problems.

Belem has a population of 1.3 million and some hotels in recent months have been offering rooms at $1,400 per night.

Some 50,000 people are expected to attend the COP30 summit in Belem.

A new meeting of COP organisers is scheduled for next week to discuss issues including accommodation.

COP30 is due to be held on November 10-21, preceded by a heads of state summit on November 6 and 7.

Austria's deficit stood at 4.7 percent of GDP in 2024, and even though that was expected to fall to 4.4 percent this year, that remains well outside the EU limit of three percent.