By Elizabeth Piper and Michael Holden

LONDON (Reuters) – Just a week after Queen Elizabeth asked Liz Truss to form a government, Britain’s new prime minister is attending services of reflection across the country with King Charles, determined to strike the right tone in her first days in power.

It has been a week like no other for the prime minister.

Her first big announcement, on only her second full day in office, had been a more than 100 billion pound package to ease the pain of spiralling energy prices. But while sitting in parliament after unveiling it, a much more dramatic statement was brought to her attention – the queen was gravely ill.

Hours later, Truss delivered a statement from outside her new Downing Street office and residence, paying tribute to the queen, who had died at her home in Scotland, plunging the country into a period of mourning.

“Queen Elizabeth II was the rock on which modern Britain was built,” Truss said then.

“She has been a personal inspiration to me and to many Britons. Her devotion to duty is an example to us all. Earlier this week, at 96, she remained determined to carry out her duties as she appointed me as her 15th prime minister.”

The queen’s appointment of her was the monarch’s last public act.

With her energy package all but on hold, although households will get the help provided from Oct. 1, Truss instead has had to help guide the nation in mourning while allowing Buckingham Palace to take the lead in its long-planned ceremonies.

So far, several lawmakers and royal observers said, so good.

“I think that she has done very well. She has come over as measured, calm and competent. She has caught the mood of the nation exactly. I am really very impressed,” said David Jones, a Conservative lawmaker and former minister.

“I am afraid the energy stuff was completely lost in the noise.”

Truss, 47, had repeatedly said during weeks of a contest to become leader of the governing Conservative Party, she was ready to govern from day one to tackle the most daunting set of challenges for an incoming leader in post-War history.

From an energy crisis, to a forecast long recession and the Conservatives behind in the opinion polls, Truss, who was appointed prime minister by the party rather than the country, and her team had barely set foot in Downing Street before they were choreographing her first big statement on fuel prices.

BILLIONS SPEECH

But despite it landing largely well, she had little time to enjoy the moment. She quickly realised the gravity of situation and holed herself up in her office to write a speech paying tribute to the queen who had reigned over Britain for 70 years.

Truss described it as a “billions” speech, according to one source close to her, referring to the fact that its reach to the world would eclipse the ones she had been giving to the party faithful in the leadership contest and also her acceptance speech to Britain outside Downing Street only two days before.

“She knew she had to get it right,” the source said.

Truss attended a service of reflection in Scotland on Monday, and will also attend services in Northern Ireland on Tuesday, and then England and Wales later in the week.

The prime minister feels it’s important to be at these services during what will be a significant moment of national mourning around the UK,” said the prime minister’s spokesman.

She also met King Charles on Friday for a one-on-one meeting, then on Saturday with her cabinet team of top ministers as well as attending the accession council that day.

Royal biographer Robert Lacey said King Charles’ leadership in mourning could buttress Truss in her new role, almost a role reversal from 1997 when Princess Diana died and then prime minister Tony Blair was at the fore, advising the queen on how to deal with the outpouring of grief.

Back in ’97, the prime minister of the day had to step in really to help and guide the monarch,” Lacey told Reuters. “I’m not saying the situation’s reversed today, but the presence of Charles actually helped strengthen Liz Truss in her new role.

But some opposition politicians say the new prime minister will have to do much more to win over voters, criticising her presentation and pointing out that even she admits she might not be “the slickest presenter.

One lawmaker from the main opposition Labour Party said other speakers in parliament had “outshone” Truss, including her predecessor Boris Johnson, who according to the Sunday Times newspaper had woken early on Friday to write his speech from scratch.

But even that lawmaker conceded she had “performed admirably” in a “challenging” week.

(Reporting by Elizabeth Piper and Michael Holden; Additional reporting by Alistair Smout; Editing by Alison Williams)