The U.S. has called out Australia’s lack of climate ambition ahead of President Joe Biden’s summit of global leaders. “Our colleagues in Australia recognize that there’s going to have to be a shift,” an unidentified senior member of the Biden administration told reporters on Wednesday, according to a White House statement. “It’s insufficient to follow the existing trajectory and hope that they will be on a course to deep decarbonization and getting to net-zero emissions by mid-century.”

The swipe comes as Australian Prime Minister Scott Morrison comes under mounting pressure to set a net-zero deadline for his nation, one of the world’s biggest fossil fuel exporters and per-capita emitters. The Biden administration will from Thursday host a virtual summit designed to extract strong emissions-reduction targets.

Biden to Vow Cutting U.S. Climate-Warming Emissions in Half

Australia is generally considered a climate laggard, even as some of its biggest markets — China, Japan and South Korea — express increased ambition to combat climate change. Morrison’s government has ruled out taxes for big emitters such as AGL Energy Ltd. and mining giants Rio Tinto Group and BHP Group, and is instead backing them to come up with the solutions to help Australia hit net zero.