The BBC Trust is expected to decide on controversial proposals to put ads on BBC.com at its May 23 meeting, the first under chairman Sir Michael Lyons.
BBC management is proposing that the BBC.com site should carry adverts for users outside the UK in an attempt to find alternative revenue sources for content paid for by UK licence fee payers.
More than 200 editorial staff signed a petition opposing the plans and backed a letter of concern sent to the BBC Trust's acting chairman, Chitra Bharucha, last month.
Staff asked the trust to consider what they described as management's "confusing and incoherent" case for advertising.
They also expressed concerns that adverts on BBC.com would undermine the corporation's editorial integrity and pave the way for further commercialisation of BBC services.
Sources inside the BBC said the BBC.com advertising plan was likely to be approved.
However, when the trust considered the proposals in February, management were asked to give more information on how the revenues would be fed back into the corporation's global news division.
The decision is likely to be made by the trust's Sir Michael, whose tenure begins on May 1.
He will face opposition from BBC staff and the National Union of Journalists, which this week stepped up its campaign against advertising on BBC.com.
The NUJ's campaign condemns the "creeping commercialisation" of the BBC, using posters of junk food and the slogan "Say no to McBBC - junk the ads".
John Smith, the chief executive of BBC Worldwide, the corporation's commercial arm, last month dismissed criticism of the plans, saying concerns about the impact of advertising had mostly come from commercial rivals.
He added that BBC Worldwide was not a public service broadcaster but a commercial organisation and would need to maintain its impartial journalism to attract "carefully selected premium advertisers".
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