A magistrate has postponed a decision on whether the Office of the Prime Minister's Chief of Staff Keith Schembri may be questioned about secret company 17 Black in a libel case instituted against former Opposition leader Simon Busuttil.

Magistrate Francesco Depasquale had been due to give a decision on Thursday, but it was postponed to give Mr Schembri’s lawyers a chance to reply to submissions by Dr Busuttil's lawyers on why he should be ordered to give evidence.

In terms of law, Mr Schembri has a right to file a reply to Dr Busuttil’s written submission, which was filed after the case had been adjourned for decree.

Mr Schembri had sued Dr Busuttil over comments he made about the Panama Papers during a public activity in March 2016.

During a hearing on January 24, Mr Schembri's lawyers objected to questions about 17 Black on the grounds that information about it came to light after the libel proceedings were instituted.

But Dr Busuttil's lawyers argued that 17 Black is a secret company named in leaked e-mails as one of two companies that would pay $2 million to Mr Schembri's and Konrad Mizzi's secret Panama companies.

The case has been put off to next month.

Correction March 8, 10.25am: The story has been updated to make it clear that the magistrate was legally obliged to give Mr Schembri time to file a written reply.