The Department of Public Works will ask the courts to rule on the validity of a R500-million building lease that the police had attempted to secure.

Public Works Minister Gwen Mahlangu-Nkabinde said at a press conference in Pretoria on Monday that she would submit the controversial Middestad Building lease to the High Court to rule on.

The lease, with property tycoon Roux Shabangu, was sharply criticised by the Public Protector, advocate Thuli Madonsela, in February because proper tender procedures had not been followed.

The police had wanted to use the building as their headquarters and Mahlangu-Nkabinde was criticised for proceeding with the lease despite receiving legal advice against doing so.

Mahlangu-Nkabinde said: "We have taken advice from the state law adviser, and that is... I must seek assistance from the High Court."

She said she would respect any decision of the High Court.

Her announcement follows the publication of a leaked copy of Madonsela's provisional report into the lease of another building in Durban – also involving Shabangu and the police.

Her announcement also follows a press conference on Friday by Shabangu, who distanced himself as a "friend" of President Jacob Zuma and said he had done nothing wrong.

At that press conference he would not comment on the Middestad lease, saying that it was possibly subject to litigation.

It was not clear whether he was referring to Mahlangu-Nkabinde's decision to submit the lease to the courts.

Public works spokesman Obakeng Modikoe said he was not aware that Shabangu had been informed of the minister's decision.

Mahlangu-Nkabinde said the papers regarding the lease would be filed with the High Court shortly.

Referring to the Sunday Times article, she said she was disappointed with media reports "based on what we consider to be a confidential government document.

"In our view these reports remain malicious and are aimed at defaming the integrity of government, the ministry and department of public works."