The BBC World Service will further reduce its shortwave transmissions next year as part of a £15m savings drive which staff have been warned will be a "real stretch".

The money will be used to invest in new TV and digital services, part of a programme called Invest to Innovate.

An extra £6.5m is being pumped into the World Service's budget this year, alongside an extra £1.5m of savings, helping to create 130 jobs. New initiatives include a global version of Radio 1's Newsbeat.

But the BBC's director of global news, Peter Horrocks, said further savings would be required in the future.

Horrocks told staff on Tuesday: "There will be a respite on editorial job cuts, for a year, but we will need significant further editorial and organisational savings in subsequent years.

"We need to save at least £15m to fund new investments across the World Service in the next three years. We have already identified about half that saving. So we need to find at least £8m extra … that is going to be a real stretch."

Horrocks said changes would include more multilingual reporting, with staff filing for their own language service and in English, as well as a further reduction in shortwave transmissions.

He said the World Service would also have to integrate further with the main BBC News operation.

Horrocks also announced that the BBC's global news division, which includes its world news TV channel, would be renamed "World Service Group … a sort of World Service-plus" and the World Service board would be axed with the change in its funding.

The new round of cuts comes after the World Service had to find £41m of savings after its budget was cut in the government's comprehensive spending review three years ago, leading to the loss of about 550 jobs.

It closed five language services, stopped radio broadcasts in seven languages, cut back on shortwave and medium-wave transmissions and axed a number of World Service English programmes.

The World Service is to be funded directly from the BBC licence fee, along with BBC Monitoring, rather than a Foreign Office direct grant, from 1 April. This switch was agreed between the BBC and the government as part of the 2010 licence fee settlement.

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