AstraZeneca said on Monday its vaccine for the novel coronavirus, developed along with the University of Oxford, could be around 90 per cent effective under one dosing regimen.
"This vaccine's efficacy and safety confirm that it will be highly effective against COVID-19 and will have an immediate impact on this public health emergency," Pascal Soriot, Astra's chief executive, said in a statement.
British Health Secretary Matt Hancock described as "fantastic news".
"These figures... show that the vaccine in the right dosage can be up to 90 per cent effective," he told Sky News, after an announcement from AstraZeneca.
"We've got 100 million doses on order and should all that go well, the bulk of the rollout will be in the new year."
The British drugmaker's preliminary trial results mark a fresh breakthrough in the fight against a pandemic that has killed nearly 1.4 million people and roiled the global economy.
Israeli gunfire killed at least 17 Palestinians and wounded dozens as thousands of displaced people approached an aid distribution site of a US-backed humanitarian group in central Gaza on Tuesday, local health authorities said.
Greta Thunberg and other pro-Palestinian activists have been taken to Tel Aviv airport ahead of their deportation, the Israeli Foreign Ministry said on Tuesday, after the Israeli navy prevented them from sailing to Gaza.
Russia launched another prolonged drone attack on Ukraine, killing one person and damaging swathes of Kyiv as well as striking a maternity ward in the southern port of Odesa, regional officials said early on Tuesday.