On reaching 100 days in 10 Downing Street this week, Rishi Sunak will double the duration of Liz Truss's brutally short term as British prime minister.

But having stabilised panicky financial markets after the calamitous Truss tenure, the Conservative leader has little to celebrate.

Double-digit inflation is fuelling a winter of misery for many in Sunak's Britain.

On Wednesday, the day before his mini-anniversary, up to half a million workers will escalate a rolling series of strikes to shut down schools, railways and other public sectors.

Opposition Labour leader Keir Starmer has been portraying the wealthy premier as "weak" and out of touch, as both parties gear up for an election likely next year.

"Is he starting to wonder if this job is just too big for him?" he told the diminutive Sunak in parliament last Wednesday.

The Labour leader was merciless as he ran the rule over Britain's state of permacrisis since Brexit and the Covid pandemic, and "sleaze" among the Conservatives.

Ambulance drivers have also been striking, joining nurses on their first-ever walkout. But Sunak is adamant that unions' pay demands will only fuel the decades-high inflation.

"Being an effective manager of public money and public services is not a sin," senior minister Michael Gove said, rejecting criticism that Sunak is an uninspiring leader after Boris Johnson, who preceded Truss.

"It is the case that first of all we have to bring the stability -- and we have -- and now we have set out areas where we are performing," he told Sky News on Sunday.

- 'Moral bankruptcy' -


Sunak faces a mountainous challenge as he bids to emulate Conservative leader John Major's surprise win over Labour in 1992.

Outside Number 10 in October, he promised "integrity, professionalism and accountability at every level" -- in pointed contrast to his two predecessors.

But Sunak has been forced on the defensive by the tax affairs of the Conservative chairman Nadhim Zahawi, who until this weekend sat in the cabinet.

Starmer on Saturday accused Sunak's Tories of "moral bankruptcy", as less well-off voters are forced this winter to choose between eating and heating.

Sunak had sought to buy time by launching an internal inquiry into Zahawi, who admitted to being "careless" with his own taxes and had to pay a seven-figure sum to the UK's tax agency -- when he was finance minister in charge of the same agency.

The inquiry's report was issued Sunday, making uncomfortable reading for both Zahawi and Sunak, who bowed to the inevitable and fired the Iraqi-born politician.

Sunak, a practising Hindu who at 42 is Britain's youngest leader since 1812, has brought a smooth-talking, technocratic approach to the premiership borne of his lucrative years in private finance.

Opinion polls show he has restored some of the Conservatives' reputation for economic competence after the short-lived "Trussonomics" experiment.

But Labour retains an average lead of 20 points overall.

- 'Flunked it' -


Tory right-wingers such as former Brexit minister David Frost accuse Sunak of lacking vision.

"Give us something to fight for," Frost wrote in The Daily Telegraph newspaper. "And bring Conservatives back to the party."

Sunak hopes to settle one running sore by reforming post-Brexit rules governing trade in Northern Ireland. A row over the protocol has paralysed self-government in Belfast.

But any deal with Brussels risks provoking Brexiteer hardliners among Tory MPs, many of whom accuse Sunak of betraying Johnson and are likely to stir trouble if local elections in May turn out badly for the party.

Tim Bale, politics professor at Queen Mary University of London and author of a forthcoming book on the Conservatives since Brexit, said Sunak had missed opportunities to carve out a fresh start from Johnson.

"Sunak may have inherited something of a poisoned chalice but he nevertheless had a real opportunity to signal a big change at the top," Bale told AFP.

"Yet even a cursory glance at the polls after his first 100 days suggests he's flunked it.

"In short, he's lived down to expectations. If I were to award him a C plus, I'd probably be erring on the side of generosity. Most voters wouldn't go any higher than a D."