Australia has joined the UK-led “Drone Coalition” to help Ukraine fight Russia, and Deputy Prime Minister Richard Marles has indicated that further support will be revealed soon, as uncertainty grows over America’s commitment to the war.

Mr Marles and UK Defence Secretary Grant Shapps also said the Australian and British militaries would upgrade ties, signing a treaty to make it easier to host each other’s forces, expand talks between senior officers, deepen intelligence-sharing and consult on emergencies that threaten security.