The number of coronavirus-related deaths in the UK has been revealed to be significantly higher than government-released figures had suggested.

New figures published by the Office for National Statistics showed there had been 210 deaths in England and Wales up to and including March 20 – while the government figure for the same period was 170 - an increase of almost 20%.

But the seemingly large disparity is easily explained by the differences in methods of counting and reporting.

The government figures - published by NHS England and Public Health Wales - only relate to deaths which occur in hospitals where a patient has been diagnosed with Covid-19.

The ONS figures for England and Wales take into consideration all deaths in which Covid-19 has been mentioned on the death certificate.

The fact that there's usually a delay of at least five days between a death occurring and it being registered also contributes to the difference in figures.

The ONS figures only take into consideration deaths which have been registered, but the government figures include all deaths that have occurred in a hospital.

The ONS has minimised the disparity caused by a difference in methods of counting and reporting by including in its figures for deaths occurring up to and on March 20, deaths which were registered up to March 25.

Separate figures by the ONS showed that of deaths registered up to March 20, 42% were people aged 85 and over, while 31% were people aged 75-84.

However, neither the ONS figures nor the government's give a real-time snapshot of the number of deaths in Covid-19 patients in the UK - nor is it an accurate reflection of exactly where we are in the "curve" of the outbreak.

  • ITV News Political Correspondent Daniel Hewitt explains why death figures differ

This is mainly because neither figure reveals exactly how many deaths have occurred each day, as they take in deaths from a range of dates.

This is usually over the previous few days, but can sometimes be from weeks earlier.

For example, the list of deaths announced by NHS England on March 29 included deaths that were recorded as taking place as far back as March 16.

This is because a death is only included in the figures once families of the victim have been informed.

As a result, the day-on-day change in the official death figures is not moving in step with how many coronavirus-related deaths are taking place in real time.

There is also a lag in ONS figures of around 11 days.

The previous ONS figures, published on March 24, had numbers up to the week ending March 13.

A third reason the official death figures do not give a real-time snapshot of where we are in the "curve" of the outbreak is due to the amount of time that can pass between somebody contracting the virus and them dying as a result of a virus-related issue.

As a result of this, any steps taken to limit the spread of the virus - such as social distancing or lockdowns - take time to show up in the number of deaths.