The government has signalled it wants to see the return of weekly bin collections across England.
The Audit Commission - which monitors local government spending - has been told to stop encouraging councils to save money with fortnightly collections.
About 160 of the 386 English local authorities collect bins fortnightly.
The Audit Commission says it does not impose inflexible rules; it merely recommends cost-effective practices.
But Communities Secretary Eric Pickles accused the watchdog of being part of a "conspiracy" to kill off weekly collections.
He said he had written to the body "requiring" it to withdraw guidance to local authorities.
He accused the previous Labour government of conspiring with civil servants to get rid of weekly collections.
No strict rules
In his letter he said: "We also had concerns over some cases of councils seemingly being 'marked down' in inspections for not adopting fortnightly collections."
He urged an end to "perverse incentives... to cut the frequency of rubbish collections" and said while it was ultimately up to councils when they collected rubbish and recycling, government should be "supporting regular and frequent rubbish and recycling collections".
The Conservatives had pledged to restore weekly collections but the coalition government is not promising any extra money to help councils do this.
The Audit Commission said it did not impose strict rules on councils and it had a responsibility to recommend the most cost-effective practices. A spokesman said it had not yet received Mr Pickles's letter.
But in response to Conservative parliamentary questions on the issue in March, its chief executive Steve Bundred said: "Without reviewing over 2,000 documents, which would only be possible at disproportionate cost, the Audit Commission is aware of only two audit, inspection or assessment reports since 2004 which recommend that a local authority considers alternate weekly collections of household rubbish."
Government sources said the department for communities and local government expected the Audit Commission to comply with Mr Pickles's request.