Last week, it was between 1.1 and 1.3.
R represents the average number of people each Covid-positive person goes on to infect. When the figure is above 1, an outbreak can grow exponentially but when it is below 1, it means the epidemic is shrinking.
An R number between 1.2 and 1.5 means that, on average, every 10 people infected will infect between 12 and 15 other people.
The number of new infections is growing by between 3 per cent and 7 per cent every day.
The latest estimates from the Office for National Statistics (ONS) suggest infection levels are at their highest since February in England.
Around one in 160 people in England are estimated to have had Covid-19 in the week to July 3.
Elsewhere, the latest figures from Public Health England (PHE) show cases of the dominant Delta variant rose by a third in the past week.
It remains the case that the majority of people being admitted to hospital in England with the Delta variant are unvaccinated, according to the PHE figures.