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.
An explosive-laden car rammed into a Pakistani military convoy on Saturday in a town near the Afghan border, killing at least 13 soldiers, sources said.
Radiation levels in the Gulf region remain normal after the 12-day Israel-Iran conflict severely damaged several nuclear facilities in Iran, Director General Rafael Mariano Grossi of the International Atomic Energy Agency (IAEA) said.
Rwanda and Democratic Republic of Congo signed a US-brokered peace agreement on Friday, raising hopes for an end to fighting that has killed thousands and displaced hundreds of thousands more this year.
The US Supreme Court on the last day of rulings for its current term gave Donald Trump his latest in a series of victories at the nation's top judicial body, one that may make it easier for him to implement contentious elements of his sweeping agenda as he tests the limits of presidential power.
Polish President Andrzej Duda arrived in Kyiv on Saturday for a meeting with Ukrainian President Volodymyr Zelenskyy, Duda's office said, as Kyiv aims to build support among allies at a critical juncture in its grinding war with Russia.