The talks with Ofcom follow talks with the previous regulator the ITC last year, which was merged to create Ofcom.
A spokesman for Five said the ITC stipulated that the channel must run a primetime news bulletin for at least 20 minutes. However Five wants to drop the slot and is now lobbying Ofcom, which is seen as a "lighter touch" regulator.
According to reports, a source at Five said that the station "simply can not sell any advertising for the 7pm news".
If the slot is axed it will leave the station with just one main daily news slot at 5.30pm supplemented by on-the-hour news bulletins throughout the evening, which last for around 90 seconds.
This would mean less of a role for star news presenter Kirsty Young. Five News is known for its relaxed approach with presenters occasionally presenting perched on their desks.
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