American officials have bought up all of the remdesivir available for July and 90% of stocks for August and September.

The US has bought up almost the entire global supply of one of two drugs used to treat coronavirus which UK patients helped test.

Remdesivir, which was developed to treat Ebola, is produced almost exclusively by US pharmaceutical giant Gilead Sciences - and it has been priced at $2,340 (£1,892) per patient in wealthier nations.

The company has agreed to send nearly all of its supply of the drug to the US over the next three months.