The BBC is to scale back the number of on-screen presenters on its news channel, with fewer on-the-ground hosts for international stories, as part of its savings plans.
The service will no longer be required to operate a "double-header" system, but will base it on editorial merit after the BBC Trust agreed to relax the stipulation.
But the Trust warned that despite efficiency savings, the channel should continue to maintain the quality of its output.
And it has been told it must find "new ways to improve and innovate".
The findings came in the governing body's review of the BBC News channel and BBC Parliament which was published today.
The Trust urged the corporation's management to keep the content and style distinctive, at a time when executives are seeking budget cuts in light of the most recent licence fee settlement.
And it praised the high quality of coverage, as well as the good value for money both services provide.
For the news channel, it found almost 20% of UK adults had watched during 2010-11, a huge rise from the 11.5% level in 2006-7.
But in a bid to cut overheads, BBC bosses have asked to be allowed to use fewer presenters. They wanted to end the present commitment for rolling news to use a presenter at the scene of major international stories in addition to a studio-based host.
The Trust agreed that it should be for channel bosses to use their judgment and should not be requirement for the £45.5 million a year station.
Today's report said the BBC should protect the "range and depth" of the news channel and executives should monitor the impact of savings on quality.
The Trust also agreed a slight reduction in the amount of business news offered by the channel. At present it is committed to it every hour, but this has been refined to just 9am to 7pm during the week.
It also called for more on-screen information for BBC Parliament to put issues into context.
BBC trustee David Liddiment said: "It is clear that News Channel and BBC Parliament users see these services as distinctive, offering coverage and perspectives they cannot find elsewhere.
"It is also encouraging that these services are so consistently providing value for money for licence fee payers.
"The past year has seen some hugely significant news stories - from the summer riots and Royal wedding at home, to the Japanese earthquake and Arab Spring uprisings abroad - and audiences tell us that for big national stories the News Channel is their 'go-to' service.
"Despite this strong performance the News Channel must keep seeking new ways to improve and innovate. There is no doubt that the marketplace for news is becoming increasingly crowded, so it is vital that the channel uses its resources wisely and maintains its distinctiveness and quality, to ensure it continues to deliver for licence fee payers."