Gross domestic product shrank by 0.1% in the third quarter and by 0.3% in the fourth, unchanged from preliminary estimates, the Office for National Statistics (ONS) said on Thursday.

Britain's economy entered a shallow recession last year, official figures confirmed on Thursday, leaving Prime Minister Rishi Sunak with a challenge to reassure voters that the economy is safe with him before an election expected later this year.

Gross domestic product shrank by 0.1% in the third quarter and by 0.3% in the fourth, unchanged from preliminary estimates, the Office for National Statistics (ONS) said on Thursday.

The figures will be disappointing for Sunak, who has been accused by the opposition Labour Party - far ahead in opinion polls - of overseeing "Rishi's recession".

"The weak starting point for GDP this year means calendar-year growth in 2024 is likely to be limited to less than 1%," said Martin Beck, chief economic advisor at EY ITEM Club."

"However, an acceleration in momentum this year remains on the cards."

Britain's economy has shown signs of starting 2024 on a stronger footing, with monthly GDP growth of 0.2% in January, and unofficial surveys suggesting growth continued in February and March.

Tax cuts announced by finance minister Jeremy Hunt and expectations of interest rate cuts are likely to help the economy in 2024.

However, Britain remains one of the slowest countries to recover from the effects of the COVID-19 pandemic. At the end of last year, its economy was just 1% bigger than in late 2019, with only Germany faring worse among Group of Seven nations.

The economy grew just 0.1% in all of 2023, its weakest performance since 2009, excluding the peak-pandemic year of 2020.

GDP per person, which has not grown since early 2022, fell by 0.6% in the fourth quarter and 0.7% across 2023.

Sterling was little changed against the dollar and the euro after the data release.