The first ODI between South Africa and England in Cape Town has been called off, less than an hour before the toss.

ESPNcricinfo understands that the postponement relates to positive Covid-19 tests within the South Africa camp, amid suggestions that protocols were breached during the T20I series.

All players and support staff are set to undergo another round of tests on Friday afternoon, in the hope of starting the series on Sunday.

A CSA statement said: "This decision results from a player from the Proteas team testing positive for Covid-19 after the teams' last round of scheduled testing performed on Thursday ahead of the ODIs.

"In the interests of the safety and well-being of both teams, match officials and all involved in the match, the acting CEO of CSA, Kugandrie Govender as well as the CEO of the ECB, Tom Harrison, have agreed to postpone the first fixture to Sunday."

The news emerged as the England team bus arrived at Newlands to begin their preparations for the match, whereupon the players immediately returned to the teams' bio-secure base at Cape Town's Vineyard hotel.

CSA and the ECB now hope to stage the three games on Sunday, Monday and Wednesday. The first game will take place at Paarl, with the second and third fixtures under lights at Newlands in Cape Town.

Kugandrie Govender, CSA's acting CEO, confirmed the news to ESPNcricinfo. "The doctors on both sides have told us that it is a perceived risk and not an actual risk, but both boards have decided that we would rather have the players not go onto the field if there is any kind of risk at all," she said. "Everybody will be tested again today and there is a 24-hour turnaround for results."

Asked what would happen if there were more positive cases, Govender said that the board would seek further medical advice, but insisted that the infected player had not come into contact with any others.

The Western Cape, where both Cape Town and Paarl are situated, has seen a resurgence in Covid-19 cases in the last few days, and as of Thursday, the region had 10,000 active cases.

Two players in the South Africa squad missed the T20I series after testing positive for the virus. CSA's chief medical officer Dr Shuaib Manjra had previously flagged that the schedule could be affected if players returned positive tests.

More to follow...