Family members write a message to two sisters who died of COVID on the National Covid Memorial wall in London, March 29, 2022. (PHOTO / AP)

LONDON - Britain's government was under-prepared and failed to anticipate measures needed to protect the vulnerable, an official inquiry heard on Tuesday, as its chair pledged to put the bereaved at the heart of her work.

Former Prime Minister Boris Johnson ordered the investigation after Britain recorded one of the world's highest death tolls. More than 175,000 deaths from the novel coronavirus had been reported by the time Johnson stood down in July last year.

As the inquiry this week hears its first evidence, it could prove a headache for Prime Minister Rishi Sunak, who was finance minister during the pandemic and faces an election next year.

This stage examines Britain's preparedness. It follows preliminary hearings after the inquiry, which is expected to last for many years, was formally launched in June 2022

"Fundamentally, in relation to significant aspects of the COVID-19 pandemic, we were taken by surprise," said the counsel to the inquiry Hugo Keith, who leads questioning.

Regarding lockdowns and shielding the vulnerable, he said: "few of those areas were anticipated, let alone considered in detail" in advance.

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"No country can be perfectly prepared, but it can certainly be under-prepared," he said at the start of module one.

This stage examines Britain's preparedness. It follows preliminary hearings after the inquiry, which is expected to last for many years, was formally launched in June 2022.

Evidence hearings on module two, covering governance and decision-making in the pandemic, are expected to begin later this year.

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The government has launched a legal challenge against the inquiry taking place in central London over its requests for internal government WhatsApp messages from Johnson's time in office that it says are "unambiguously irrelevant".

The inquiry says it is for the chair to determine what material is relevant. The legal case will be heard around the end of June.

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Inquiry chair Heather Hallett said her focus is "those who have suffered hardship and loss are and will always be at the heart of the inquiry".

"I am listening to them. Their loss will be recognized," she said.