London Marathon organisers have revealed more details about plans to stage a two-day event next year which they say would be an “incredible celebration” that would raise more than £130m for charity and bring in £400m in social and economic benefits.

As the Guardian revealed last month, advanced talks are under way for the one-off event which would allow around 100,000 people to take part, nearly double the number running on Sunday.

Speaking on Wednesday, Hugh Brasher, the event director, confirmed that one of the two days would be devoted to faster women, with the women’s elite race, women’s championship and good-for-age runners and a mixed mass participation race all taking place. The other day would then focus more on the men’s races while also having a second mass participation race for men and women.

Brasher also promised those still holding up the deal that 2027 would be a one-off “double” as the London Marathon did not want to “lose the love” it has from runners, fans and people living in the capital.

“We have a huge amount of plans for it,” said Brasher. “We believe that more than £130m would be raised for good causes, and that £400m of economic and social benefit would come to this country – that’s from research done at Sheffield Hallam [University]. We think it would be absolutely amazing. And it is something that we’ve been working on for a long time.

“The idea was also overwhelmingly positively received. But you have to bear in mind that the London Marathon has been going for 45 years and it’s got to a position of love, not only the sporting calendar but the calendar of London.

“You can lose that love, and we have to be mindful of that. And that is why it is very much a one and done. But there is a need in this country to do it.”

Brasher also confirmed talks have been had with the BBC to ensure both days would receive significant coverage and further consultations would be taking place this week and next to hopefully get the plans signed off.

“There has to be a huge amount of consultation, absolutely rightly, whether it’s the police, whether it’s the fire [service], whether it’s ambulances, whether it’s the boroughs, whether it’s TfL [Transport for London], whether it’s the mayor, whether it’s private landowners,” said Brasher.

“There are conversations going on this week, next week. We do hope we will get signed off, but it is a huge undertaking, not only from our team’s point of view, but also London’s point of view.”