Brewers blame poor crops of hops and barley caused by a wet summer for a predicted price rise.
And now a powerful committee of MPs is pressing for beer tax to be slashed to compensate for the increase.
Stephen Crawley, of the Caledonian Brewery, said: "The brewers have never known raw material prices to increase the way they are at the moment. We will see the £4 pint in 2008."
There are fears the increase of around £1 on London prices will lead hundreds of pubs to close.
Paul Waterson, of the Licensed Trade Association, said: "We have been a nation of take-home drinkers for some time, because of artificially low prices in the supermarket. More price rises will mean the death knell for hundreds of pubs."
The Environment, Food and Rural Affairs select committee is pressing for a cut in duty to help deal with "agflation" -that's rising food and drink prices.
A spokesman said: "We are trying to establish what can be done with the tax system to bring the issue of agflation under control."