BP is more than halving the size of its senior management team as part of chief executive Bernard Looney's drive to make the 111-year-old oil company more nimble as it prepares for the shift to low-carbon energy, company sources told Reuters. 

Under BP's new business structure the number of leadership roles will drop to about 120 from 250.

Many veteran executives who held key positions under former chief executive Bob Dudley are set to leave in the coming months, the sources said. 

Bernard Looney said in February he was creating 11 divisions to "reinvent" BP and dismantle its traditional structure dominated by an oil and gas production business, known as upstream, and a refining, marketing and trading division, known as downstream. 

In emails sent to staff on May 14 seen by Reuters, Looney named over 100 so-called Tier 2 managers who will form the leadership teams of the 11 divisions under the new, streamlined management structure. 

"We expect the reinvented bp to be smaller and nimbler. We have already started by removing a layer of management at Tier 1 and 2," Looney said in an email to staff. 

BP has confirmed to Reuters the senior appointments detailed in the emails. 

The changes mean that in many cases a whole management layer is being stripped out. 

For example, Starlee Sykes, who remains head of production for the Gulf of Mexico and Canada, is now two steps removed from Looney whereas before it was three. 

The appointments marked Looney's first 100 days in office, which have been dominated by a collapse in oil prices due to the coronavirus pandemic that has forced energy companies to rein in costs across the board. 

"This situation feels all-consuming right now. But work has not stopped on our plans to reinvent bp," Looney told staff.

"In fact, the spread of Covid-19 has only strengthened our resolve to progress our transformation plans," he added. 

In April, BP cut its budget by 25% to $12 billion and said it would find $2.5 billion in cost savings by the end of 2021 through the digitalisation and integration of its businesses.

The London-based company, however, maintained its planned $500m investment in renewables and low-carbon technology amid expectations of only a slow recovery in oil demand. 

BP did not provide details about planned job cuts then and told the company's 70,100 employees that any reductions would be frozen for three months in the wake of the pandemic. 

"We'll provide more information on the redundancy freeze in June," Looney said in his email to employees. 

BP said it will provide details of its new long-term strategy at an event for investors in September.

For years, BP's structure has been dominated by the upstream and downstream divisions, as has been the case at all major integrated oil companies such as Exxon Mobil and Royal Dutch Shell. 

The new structure with 11 divisions comes into force on July 1 and is designed to help BP shift from oil and gas towards solar and wind power and low-carbon technologies. 

"Together we will work hard to build a more modern, focused and integrated company - one that is well-positioned to meet the challenges and seize the opportunities that lie ahead," Looney told staff. 

Most of the upstream and downstream operations now come under one production and operations group, which is headed by Gordon Birrell and includes 14 senior managers, according to the announcement. 

High-profile departures include Michael Townsend, BP's regional president for the Middle East, and Hesham Mekawi, president for North Africa.