The UN secretary general has said that “climate change is out of control”, as an unofficial analysis of data showed that average world temperatures in the seven days to Wednesday were the hottest week on record.

“If we persist in delaying key measures that are needed, I think we are moving into a catastrophic situation, as the last two records in temperature demonstrates,” António Guterres said, referring to the world temperature records broken on Monday and Tuesday.

The average global air temperature was 17.18C (62.9F) on Tuesday, according to data collated by the US National Centers for Environmental Prediction (NCEP), surpassing the record 17.01C reached on Monday.