The 1% decline was for underlying revenues (excluding discontinued operations) the 11 weeks to 18 September with the same period a year ago.
The figures were disclosed by DMGT, the company behind the publisher of the Daily Mail, the Mail on Sunday and Metro, ahead of its financial year end on 2 October.
For the 11-month period to the end of August 2011 Associated's ad revenues were down 1% on an underlying basis and down 2% on a reported basis.
Underlying circulation revenues in the 11 weeks to 18 September were down 4%, which was put down to temporary price discounting on The Mail on Sunday, offset by the 5p increase in the Daily Mail's cover price in July.
However, Associated claimed both the Daily Mail and The Mail on Sunday have increased their market share in the wake of the News of the World's closure in June.
Print ad revenues fell by 4% across Associated Newspapers, with retail and travel ads down by 5%.
DMGT's regional newspaper arm, Northcliffe Media, did not reflect the improvement in ad revenues at the national newspapers.
In the 11 weeks to 18 September, Northcliffe ad revenues were down 11%, compared with a 10% drop in the previous quarter.
For the 11-month period to the end of August 2011 Northcliffe's ad revenues were down 10% and circulation revenues were down 7%, leaving total revenues down 10%.
Northcliffe has reduced its staff headcount by 17% over the period from 3,130 to 2,600 employees.
Martin Morgan, chief executive of DMGT, said: "Despite our continued focus on operational efficiency, the weak consumer advertising environment means that full year group operating profit will be lower than last year.
"We expect some growth in earnings per share compared to last year, given lower finance and tax costs, but at the lower end of market expectations.
"Going forward our focus will remain on driving organic growth, operational and financial efficiency and pursuing an active portfolio management approach."
DMGT's overall revenues, which include the contribution of business-to-business operations such as Euromoney Institutional Investor, were up 1% on a reported basis and up 2% on an underlying basis.