The Federal Court registrar has asked opposition leader Anwar Ibrahim’s lawyers to prepare submissions for his sentencing.

While his lawyers described this as normal, international observer and Queen’s Counsel Mark Trowell sees this as a "bad omen".

"It suggests that the defence's appeal against the conviction and sentence will be refused.

"If that is so, Anwar will immediately be taken into custody," Trowell (left) told Malaysiakini.

The Federal Court will deliver its verdict tomorrow on Anwar’s final appeal against his sodomy conviction and five-year jail sentence.

The prosecution, on the other hand, is appealing for a heavier punishment.

Malaysiakini learnt that Anwar's lawyers were told to prepare the sentencing submissions after being informed of the verdict date.

Anwar's counsel Sangeet Kaur Deo confirmed with Malaysiakini that the lawyers have been asked to provide written submissions.

"It is not necessarily a bad sign as it is standard practice to inform parties to be ready for the hearing of any appeal," Sangeet said.

Anwar was convicted of sodomising his former aide Mohd Saiful Bukhari Azlan (right) at the Desa Damansara condominium in Kuala Lumpur between 3.15pm and 4.30pm on June 26, 2008.

The five-year jail term is the minimum punishment for a charge under Section 377B of the Penal Code, which is for carnal intercourse against the order of nature.

If the court decides to enhance the sentence, Anwar could be slapped with the maximum jail sentence of 20 years.

The seven-year legal battle saw 27 prosecution and eight defence witnesses, including Anwar, taking the stand.

The case also saw Anwar changing lead counsels three times, with the first being senior lawyer Sulaiman Abdullah.

Following this, the defence was led by Karpal Singh until his death in an accident last year.

Anwar then surprised the nation with the appointment of former Federal Court judge Gopal Sri Ram as his lead counsel last October.

Gopal, who led a team of 14 lawyers, had punched numerous holes in the prosecution's case, mainly attacking Saiful's credibility as the star witness.

The prosecution, meanwhile, is led by Muhammad Shafee Abdullah.

Shafee was not the original prosecutor when Anwar was charged as well as during the trial at the Kuala Lumpur High Court, where the task then was entrusted to former solicitor-general II Mohd Yusof Zainal Abiden.

Yusof retired after Anwar was acquitted by the High Court in February 2012.