LONDON — The U.K. will not contribute public money to a flagship tropical forests fund which Brazil wants to make a centerpiece of its COP30 climate summit.

A spokesperson for the Department for Energy Security and Net Zero told POLITICO the U.K. was “incredibly supportive” of the initiative, known as the Tropical Forests Forever Facility (TFFF) — but that support would continue with “efforts to unlock private investment.”

The decision risks disappointing Brazilian President Luiz Inácio Lula da Silva, a close ally of U.K Prime Minister Keir Starmer, who is due to attend the COP30 leaders’ summit in the Amazon city of Belèm on Thursday. Brazil has pledged $1 billion to the fund.

British ministers had been split over whether the U.K. could commit taxpayers’ money to the plan, given straitened finances at home.

Chancellor Rachel Reeves’ Budget later this month is widely expected to raise taxes. Given this backdrop, Treasury officials and some in 10 Downing Street had pushed back against the U.K. contributing financially, despite support for the scheme from Energy Secretary Ed Miliband and Deputy Prime Minister David Lammy.

It is hoped the TFFF fund could ultimately reach $125 billion, primarily from private investors. Brazil had initially hoped governments would provide an important initial capital base of $25 billion, although Brazilian officials have started to downgrade those expectations, according to reports.

Investors would receive a return, while the fund would also channel money to countries that protect their tropical forests from deforestation.

A DESNZ spokesperson said: “The U.K. is incredibly supportive of the Tropical Forests Forever Facility and is proud to have played a part in assisting Brazil to develop the initiative.

“That support will continue, including by efforts to unlock private investment for the facility.”