Siemens chief executive Joe Kaeser also met Luisa Neubauer, the 23-year-old activist who has become the face of the German movement. A company spokesman said she had been invited to discuss the issue with him. The protests centre on controversial plans by Indian industrial group Adani to build one of the world's largest coal mines in central Queensland, with Siemens contracted to provide a rail signalling system for the project. The company has come under pressure as a partner in the project and as a result Mr Kaeser agreed in December to reassess the contract, which is said to be worth about €20 million ($32 million). A decision could be made any day now, according to company sources. Fridays for Future protesters march through Munich's centre after a protest outside the headquarters of German engineering conglomerate Siemens which has a contract to provide systems to the Adani mine in Queensland. Credit:Getty Images

"We take the issue very seriously and are taking the time necessary to hear and discuss different perspectives," a Siemens spokesman said. A spokeswoman for Adani in Australia said they were "pleased to be working with Siemens as the company is known for its exceptional experience in building rail signalling infrastructure around the world”. Loading “After a comprehensive competitive process, we have contacted Siemens because of their extensive experience providing signalling systems that will ensure the safety of train drivers and workers who will operate our new rail network in central Queensland,” she said. Australian climate activists have for years been voicing their opposition to the mine, which would yield up to 60 million tonnes of coal a year.

Nick Heubeck, a Fridays for Future activist, was optimistic about the company's invitation to discuss the matter. "We have built up so much pressure in Germany and Australia that we could imagine Siemens taking what we see as the sensible decision in light of a sum of €20 million," he said. Australian conservation and climate action groups were also protesting on Friday in Sydney and Melbourne. A "Stop Adani" campaign opposes Siemens' involvement, which it says is central to Adani's plans to access the Galilee coal basin, where there are currently no coal mines. "The eyes of the world have been on Australia as climate change has fuelled the worst bushfire season we have ever experienced," said Christian Slattery, a senior campaigner for the Australian Conservation Foundation.

Loading Replay Replay video Play video Play video "It is shameful that Siemens would choose to support a coal mine that will make future bushfires even worse." Protesters also took to the streets in other cities around the world on Friday to protest against climate change in the face of the Australian bushfires. In Washington, Veteran activist and actor Jane Fonda was joined by fellow Hollywood stars Joaquin Phoenix and Martin Sheen at the foot of the US Capitol building, where they demanded action on climate change alongside other protesters. "The climate crisis makes our nation and all nations less secure," said Fonda who also spoke about the bushfires.

Actress and activist Jane Fonda talks with actor Martin Sheen outside the US Capitol during a protest on climate change on Friday. Credit:AP Clad in her signature red hat and coat, clenched fist raised high, Fonda saluted the sea of chanting people who had gathered for her final "Fire Drill Friday". She cheered as 147 of them were arrested on the steps of the Capitol building and then marched down Pennsylvania Avenue to the Chase Bank branch where environmentalist Bill McKibben and about two dozen fellow activists had staked out in protest against the bank's financing of oil and gas companies. "Move your money Chase, or we'll move ours. Fossil fuels have got to go," the demonstrators shouted, as police filed into the bank to apprehend McKibben and nine others. In London, protesters sent the message straight to Australia House, where about 1000 people gathered to warn that climate change had wrapped itself around the Australian summer.

More than 10 million hectares of land have burnt in Australia since September, which is early for the bushfire season. At least 26 people have died and several thousand homes destroyed. DPA, Washington Post, with Jocelyn Garcia