The National Accountability Bureau's (NAB) prosecutor in the Avenfield reference against former prime minister Nawaz Sharif's family on Monday lashed out at defence counsel Khawaja Harris for "needlessly questioning" the prosecution witness regarding documents that were not part of the court's record.

"Mr Khawaja is basing his questions on documents that we [the court] are not considering [as part of the case record]," NAB prosecutor Sardar Muzaffar complained during Monday's hearing.

He insisted that the cross-examination of the prosecution's witness be limited to "relevant facts".

The argument between the two lawyers occurred when Harris was cross-questioning Wajid Zia, who had headed the joint investigation team (JIT) tasked with collecting evidence in the Panama Papers case by the Supreme Court.

Harris had questioned Zia about his communication with international law firm Guernica, which was hired by the JIT during the investigation of Panama Papers case and which had provided Nawaz's iqama as well as Capital FZE's trading license.

The JIT's communication with the law firm had not been included in the JIT report, nor had it been exhibited in court as evidence, since it was classified as a source document.

Objecting to Harris' line of questioning, the NAB prosecutor said it was unprecedented to allow the defence to refer source documents during its cross-questioning.

Muzaffar complained that Harris had asked "similar questions 15 times", to which the latter replied that he had to ask the same thing in different ways "to ferret out the truth."

"It has been 11 days yet his [the defence counsel's] cross-questioning has not come to an end," Muzaffar countered. "He does not want to get to the truth, he wants to intimidate [the witness]," he complained.

The court subsequently upheld Muzaffar's objection and forbade Harris from questioning Zia about documents that were not part of the court's record.