Iran's official daily coronavirus caseload exceeded 6,000 infections on Friday, setting another record this week, as death rates also remained close to the country's all-time high.

Health ministry spokeswoman Sima Sadat Lari said Iran had registered 6,134 new infections in the past 24 hours, raising the total to 556,891.

The previous record of 5,616 was announced on Wednesday, a day after Iran breached 5,000 new daily cases for the first time.

Lari also announced 335 new virus deaths on Friday, barely below the record of 337 registered on Monday.

The new fatalities bring officially reported Covid-19 deaths in the Middle East's worst-hit country to 31,985.

Deaths and infections from the novel coronavirus have been on a rising trajectory in the Islamic republic, which has recorded several new highs since September.

According to Lari, 27 of Iran's 31 provinces are currently "red" -- the highest risk level on the country's colour-coded scale.