LONDON, Nov 3 (Reuters) - A climate finance platform co-founded by MUFG, Japan's biggest financial group, has raised an initial $600 million to help countries in developing markets adapt to the impacts of climate change and cut emissions, executives told Reuters.

The announcement comes as business leaders gather in Brazil ahead of the COP30 climate talks with countries being urged to do more to close a UN-estimated finance gap of $300 billion a year, including by billionaire investor Bill Gates.

As extreme weather events such as floods and droughts increase in intensity, the GAIA Climate Loan Fund would primarily aim to back projects that help countries build resilience.

"Adaptation Finance is a topic that has been on the rise at the last few COPs," said Ariane Pevide, Director, Climate and Blended Finance at MUFG, in emailed comments.

"We hope that the close of GAIA will strengthen the argument for private sector capital, focused on adaptation as a blueprint for the market."

FinDev Canada, Canada's development finance body, and the Green Climate Fund, the world's biggest dedicated climate fund, also provided investments and the fund aims to grow to $1.5 billion.