As far as I could work out you can only ask - but not demand - that they take it off the market. With the likes of rightmove, zoopla etc you'll be lucky if they change it to 'Sold STC' within a week of the offer being accepted. Also, regardless of whether it's taken off the market, the agent is apparently legally obliged to forward any offers to the vendor.
That said, there were plenty of places I tried to view and despite the status on property websites was told that they were under offer. Even had viewings cancelled at almost no notice for the same reason.
As far as I could work out you can only ask - but not demand - that they take it off the market. With the likes of rightmove, zoopla etc you'll be lucky if they change it to 'Sold STC' within a week of the offer being accepted. Also, regardless of whether it's taken off the market, the agent is apparently legally obliged to forward any offers to the vendor.
That said, there were plenty of places I tried to view and despite the status on property websites was told that they were under offer. Even had viewings cancelled at almost no notice for the same reason.
Good luck!