MPs have called on the Chancellor to return to giving just one Budget statement a year.
Members of the Treasury Committee said the Autumn Statement had taken on the characteristics of a second Budget and brought about uncertainty and additional costs to business and the economy, the BBC reports.
The Treasury said it would consider the report and respond in "the usual way".
"The primacy of the Budget as the main focus of fiscal and economic policy making should be re-established," the MPs said.
The BBC said the Autumn Statement had traditionally been used as an update on the general state of public finances, but since Gordon Brown's stint as Chancellor it was increasingly used to announce tax changes and policy.
The report also said the MPs had questioned the track record of the Office for Budget Responsibility (OBR), set up in 2010 to provide independent forecasts for the economy and public finances.
They said its forecasts had been overly optimistic and often had to be revised down.
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