Western leaders meeting at the G-20 summit in South Africa said Saturday that the unilateral U.S. proposal to end the war in Ukraine provides “a starting point” but will need “additional work”.

"We are clear on the principle that borders must not be changed by force. We are also concerned by the proposed limitations on Ukraine's armed forces, which would leave Ukraine vulnerable to future attack," the leaders of key European countries as well as Canada and Japan said in a joint statement.

“We will continue to coordinate closely with Ukraine and the U.S. over the coming days,” the statement added.

The plan’s elements relating to EU and NATO would need their consent, according to the statement.

The 28-point blueprint to end the Kremlin's aggression sparked alarm in Kyiv and European capitals, with Ukrainian President Volodymyr Zelenskyy saying Friday that his country could face a stark choice between standing up for its sovereign rights and preserving the American support it needs.