The Mail&Guardian newspaper has criticised the presidency for releasing a statement on an exclusive story set to appear on its front page on Friday.

"By effectively breaking our story in advance, and robbing us of exclusivity, the presidency has damaged the relationship of trust that we had developed with officials there," said M&G editor-in-chief, Nic Dawes in a statement.

The presidency issued a statement on Thursday, saying President Jacob Zuma was not using taxpayer's money to foot the bill for an expansion to his Nkandla homestead.

The M&G said this followed an attempt to obtain comment from the presidency about the construction, giving it a fair chance to respond.

The statement was issued late on Thursday afternoon, just before the paper's deadline.

The M&G said it was a "clear attempt to limit the impact" of the story.

The paper discovered the construction work during a visit to Nkandla at the weekend and had established details of large new houses, a clinic and helipad being built.

It approached both the presidency and the public works department for comment. The former refused to respond and the latter "untruthfully insisted" that no building was underway.

"Competition is an important part of a vibrant media landscape, and the drive to secure scoops is an important energising factor in our constitutionally prescribed work. Skilled communicators understand this, and realise that they need to be able to work with us.

"If government communicators make it impossible for us to trust them with basic courtesy, we will struggle to share information with them, and two things will suffer: their ability to shape our opinions, and the willingness of journalists to seek all sides of every story. Ultimately, that is bad for democracy," Dawes said.

Read the official press release.