W&K will launch the online versions of the Daily Mail (dailymail.co.uk) and The Mail on Sunday (mailonsunday.co.uk), while also tasked with handling advertising for ANM's existing websites ThisIsTravel.co.uk, Homes and Property and the search directory UKPlus. The agency already handles Associated's Loot brand.
DLKW, meanwhile, will manage the Evening Standard website, ThisIsLondon, along with londonjobs.co.uk and ThisIsMoney. The websites were all previously handled by DSJ-SW.
The newly acquired Jobsite, which ANM bought last week for £35 million, has not been handed to either agency.
Robert Cooke, the head of marketing at ANM, said: "We have appointed two agencies, as it is a better way of gaining focus when you have a multi-brand portfolio. Splitting the account means you get the best out of both agencies given their indigenous knowledge and skill base."
The planning and buying account for ANM will be handled by Starcom Media-Vest Group.
ANM is part of the Daily Mail owner, Associated Newspapers, which also publishes Metro. Banks Hoggins O'Shea/FCB handles advertising for the Daily Mail, Bartle Bogle Hegarty manages The Mail on Sunday, while Barrett Cernis is the retained agency for Metro.
Neil Christie, the managing director of W&K, said: "We are very pleased to be working with ANM and relish the task ahead. We can't wait to get started."