Workers for Rolls-Royce have been left fearing for their jobs after bosses are reportedly going to axe more than 4,000 jobs, it has been reported.

The jobs losses would be aimed at cutting costs and increasing profits, with middle managers and back-office staff thought to be most affected, reports the Sunday Times.

The newspaper says chief executive Warren East will announce the job losses at an analyst briefing on Friday, dealing a "devastating blow" to its Derbyshire base.

The cuts are expected over several years - although Unite the Union said that the claim was "pure speculation".

In a deal struck with unions last year, Rolls-Royce pledged to safeguard about 7,000 British jobs by not making any compulsory redundancies among its engineers for five years.

Rolls-Royce in Derbyshire could axe 4,000 jobs

However, that agreement doesn't protect white-collar managers across finance, human resources and purchasing departments - largely based in Derby.

Mr East has long argued that Rolls-Royce is bloated with unnecessary costs, duplicated roles and too many layers of management.

The speculation comes only two months after the company announced it was back in profit after bouncing back from its worst ever financial performance.

The firm, which has its Civil Aerospace and Nuclear divisions in Derby, reported pre-tax profit of £4.9 billion.

This is a marked contrast to a year ago when Rolls-Royce – the city's largest private-sector employer with about 14,000 staff – reported its worst performance in its history.

In April last year, the company posted a £4.6 billion pre-tax loss for 2016 due to a combination of a weaker pound and the impact of a £671 million settlement with regulators for past bribery and corruption cases.

Rolls-Royce's profits for 2017 could have been higher had it not been for some "in-service" issues with two of its aero engines – the Trent 1000 and Trent 900.

The problems related to parts wearing out quicker than expected on the engines. This resulted in the firm redesigning the affected components. In all, Rolls-Royce took a £227 million hit from these issues.

There was better news for the company in terms of sales, with revenues rising to £16.3 billion, a rise of nine per cent. However, the firm's order book dipped by three per cent to £78.5 billion.

Despite this, Mr East said he was pleased with the progress the firm had made over the past 12 months.

Speaking two months ago, he said: "Rolls-Royce made good progress in 2017. Financial results were ahead of our expectations and we achieved a number of important operational and technological milestones, but were impacted by the increasing cost and challenge of managing significant in-service engine issues.

Rolls-Royce chief executive Warren East
Rolls-Royce chief executive Warren East

"We are encouraged by the improving financial performance in 2017 with growing revenues contributing to improved profitability and cash generation.

"Looking forward, sustaining this improvement and delivering increasing cash flow generation will strengthen our position as one of the world's leading industrial technology companies."

Rolls-Royce is made up of a number of businesses – two of which have a presence in Derby – Civil Aerospace and Nuclear.

In terms of the upsurge in Rolls-Royce's fortunes, these Derby businesses are playing a key role.

At Civil Aerospace, over the past 12 months, progress has been made on three key engine programmes – the Trent 1000 TEN, the Trent XWB-97 and the Trent 7000.

Not only that, the firm announced a major investment in the Sinfin site. It is pushing ahead with modernisation plans to create an "aerospace campus" and has received permission to build a new £90 million test bed at the site.

At its Nuclear site in Raynesway, it has been given permission to expand its Primary Component Operations building and construct a four-storey office building, which would contain 400 workstations and add 200 parking spaces.

Civil Aerospace is the largest of all Rolls-Royce's businesses, accounting for the majority of the firm's sales.

In terms of its performance, Rolls-Royce's financial results show that its sales stood at £8 billion – a 14 per cent improvement on the previous year, while profits increased by an impressive 42 per cent to £520 million.

A key achievement for the division was the number of engines delivered in 2017, which increased by five per cent to 683.