Sunak has joined former British leaders Boris Johnson and Liz Truss in providing strong support to Ukraine, including through the delivery of weapons and training of troops.
It has so far refused to send fighter jets but Sunak said on Saturday that Britain could help in other ways.
“Where other countries are able to provide aircraft immediately, the United Kingdom will happily support them in doing that,” he told the annual Munich Security Conference.
He also said Western allies should consider how to ensure that Russia pays towards the reconstruction of Ukraine once the war has ended, and said the global community needed to recognise that a new framework was required to maintain long-term security.
“From human rights to reckless nuclear threats, from Georgia to Moldova, Russia has committed violation after violation against countries outside the collective security of Nato,” he said.
“And the international community’s response has not been strong enough.”