The corruption trial against former Malaysian premier Najib Razak, who allegedly misappropriated RM42 million from a unit of state fund 1Malaysia Development Berhad (1MDB), is at the tail end of the prosecution's case, with the defence expected to wrap up its cross-examination of the last prosecution witness early next week.

The trial will then move on to the much-anticipated hearing of Najib's alleged connection with the misappropriation funds from 1MDB.

The court heard from the 57th prosecution witness, Malaysian Anti-Corruption Commission investigating officer Rosli Hussain, that RM3.3 million was charged to Najib's credit card at a Swiss jewellery outlet in Italy on Aug 14, 2014. But Mr Rosli said it was a "mere claim" when asked by the defence if the gift was for the wife of former Qatar premier Hamad Jassim Jaber al-Thani.

Defence counsel Farhan Read then produced a letter dated Aug 15, 2014, purportedly addressed to Najib's wife Rosmah Mansor, from Noor Abdulaziz Abdulla Turki Al-Subaie, the sheik's wife, to express her appreciation for the gift.

In response, Mr Rosli said: "Rosmah had never mentioned to me this letter."

SRC, a former unit of 1MDB, had received RM4 billion (S$1.33 billion) in loans from the civil servant pension fund, KWAP, the court heard.

The loans were guaranteed by the finance ministry, when Najib was the minister.

Of this sum, RM42 million was then channelled into Najib's personal accounts. The prosecution had detailed this month how the money was used for private spending, including the purchase of designer items, luxury jewellery, and hotel stays.

Najib's counsel this week attempted to pin the blame on fugitive financier Low Taek Jho, or Jho Low.

Mr Rosli, however, dismissed all suggestions which implied that it was Mr Low who had misappropriated the funds deposited in Najib's personal AmBank accounts, by asserting that the businessman had not benefited from the SRC funds, according to his investigation.

Earlier Friday, the court also heard from Mr Rosli that his officers had taken Mr Low's statement in Abu Dhabi on Nov 27, 2015, as well as SRC International Sdn Bhd former CEO Nik Faisal Ariff Kamil's statement in Jakarta on Oct 17 the same year.

But the biggest highlight throughout the case has been the amount of power the former premier had when he was the prime minister of Malaysia, coupled with the direct involvement of Mr Low with Najib's personal finances, which painted Najib as the puppet-master.

A key witness, former SRC director Datuk Suboh Md Yassin, had also told the court under cross-examination that Mr Faisal was capable of forging signatures to expedite the movement of millions of ringgit as he had the backing of someone powerful.

Mr Suboh also claimed that in 2015, he was forced to hide in Bangkok and Abu Dhabi after he was directed to go abroad by an unknown individual who claimed to be a representative from the Malaysian Anti-Corruption Commission and not meet its officers.

In 2015, he had told a recording officer that all signatures instructing AmBank to conduct real-time electronic transfers and securities automatic transactions were his but in May last year, he changed his statement when two recording officers visited him at a hotel, saying that the signatures had been falsified.