Emails from private accounts and texts sent by the prime minister and cabinet members could be accessible under the Freedom of Information Act (FOI).
New government guidance will say the act relates to "the nature of the information and not the format".
The shift is revealed in a Department for Education letter, abandoning a two-year dispute with the Information Commissioner related to private emails.
The 2000 act aimed to make government more open and accessible.
For almost the last two years, Education Secretary Michael Gove has been in dispute with Information Commissioner Christopher Graham, over whether Mr Gove's private emails were accessible under the Freedom of Information Act.
A message sent from a private account by Mr Gove in December 2010 had been obtained and published by the Financial Times.
The BBC has seen a letter to the commissioner from the director of law and information rights at the Department for Education, Claire Johnston, outlining that the department will give up its dispute over releasing details of emails sent from Mr Gove's private account.
It also reveals that new guidance on the scope of the Freedom of Information Act will be published by the Cabinet Office "shortly".
The initial row centred on whether it was legitimate for communication via private email accounts to be accessed by journalists and others if they made a request under the Freedom of Information Act.
Mr Gove and his advisers insisted they were acting in good faith and - in line with the codes for ministers and special advisers - they did not wish to conduct political, as opposed to departmental, conversations on government computers.
The letter discloses that the new guidance from the Cabinet Office is at "an advanced state and nearing publication".
A spokeswoman for the Cabinet Office told me: "The guidance will make clear that whether or not information is subject to the Freedom of Information Act depends on the nature of the information and not the format in which it is held.
"Government information held on private email accounts is within scope of the Freedom of Information Act."
This, potentially, raises the prospect of communication via text between, say, the prime minister and the deputy prime minister, being requested under the act if it related to government business.
"The question of how the Freedom of Information Act applies to information held on private email accounts is a complex area of the law, on which the Information Commissioner's Office has issued guidance.
"The Cabinet Office is preparing guidance on how this applies to Central Government Departments, and this will be published shortly," the statement adds.
There will be those who question whether the potential for much greater disclosure will be in the interests of well-functioning government.
In his memoirs, former Prime Minister Tony Blair was particularly outspoken about the Freedom of Information Act, a law introduced when he was in Downing Street.
"You idiot. You naive, foolish, irresponsible nincompoop. There is really no description of stupidity, no matter how vivid, that is adequate. I quake at the imbecility of it," he wrote.
"For political leaders, it's like saying to someone who is hitting you over the head with a stick, 'Hey, try this instead,' and handing them a mallet."