United States government facilities will re-open on Friday after unexpected closures this week for security reasons, US embassy spokesperson Sharon Hudson-Dean said on Thursday.

Operations were closed on Tuesday so that they could deal with an undisclosed security issue.

Hudson-Dean said she could not comment on details of the potential threat or what action was taken.

A message posted on the website of the US diplomatic mission to South Africa read: "The US mission wishes to express its appreciation to the South African Government, and in particular the South African Police Service (SAPS) Division: Crime Intelligence, for outstanding cooperation and support.

"The many good wishes received from the South African public are also deeply appreciated by the US mission." - Sapa