The government may take direct control of libraries if councils are overzealous in closures.
The Sunday Times, quoting Whitehall sources, said the government is concerned some communities, particularly rural ones, may end up with no access to library services. It is also worried about the effects of the closures on children and the elderly.
Library campaigners have estimated up to 1,000 libraries may be at risk.
The sector has recently come under threat in Manchester, where the council last week announced plans to close five branches. Libraries in Sandown, Ventnor, Freshwater and Cowes on the Isle of Wight could see their opening hours cut to one day a week and closed after a year.
One government source told the newspaper: "At this stage we want to offer advice. We are reminding councils what their statutory responsibilites are. We can't do anything during the consultation, which is still happening. We then have statutory powers to intervene if it is thought necessary."