British Prime Minister Rishi Sunak is expected to launch a mini reshuffle on Tuesday, breaking up two departments to better suit his pledge to spur the economy and turn around his party's fortunes before an election expected next year.

Sources confirmed reports from the Sun and the Times newspapers late on Monday that there were plans to break up the department for Business, Energy and Industrial Strategy (BEIS)and the department for Digital, Culture, Media and Sport (DCMS).

The timing surprised some in his party, but after firing his party chairman over his tax affairs and with an investigation into bullying allegations against his deputy prime minister, Dominic Raab ongoing, several lawmakers said he might be seizing a chance to stamp his mark on his government.

Raab denies the allegations.

One source said Sunak was planning to merge the business arm of BEIS with the trade department and to create a new science and digital unit by bringing together the digital arm of DCMS with the science and innovation part of BEIS.

He was also expected to name the new chair of the party, a position made ever more important before the next national election expected in 2024, after Nadhim Zahawi was sacked over his tax affairs.

Downing Street declined to comment.

Since entering Downing Street in October, Sunak has been under pressure to stamp his authority not only on his government but also over his party, which ousted two prime ministers last year over scandal and economic chaos.

He has so far failed to reduce the commanding lead in the opinion polls held by the opposition Labour Party, which is increasingly presenting itself as Britain's next government.

He promised in January to tackle Britain's most serious problems, from cutting inflation to reducing illegal migration, in a move aimed at convincing his lawmakers he can lead them into the next election.