One of the four al-Jazeera journalists jailed in Egypt, Mohamed Fahmy, has been given a press freedom award, before the seventh session of his trial on Saturday.

The Canadian Committee for World Press Freedom said it had awarded the prize to Fahmy, a Canadian-Egyptian and the Cairo bureau chief for al-Jazeera English, in recognition of the battle he has fought for free speech since being detained with two colleagues in late December.

Fahmy, an ex-CNN journalist; Peter Greste, an Australian former BBC reporter; and a local producer, Baher Mohamed, are accused of smearing Egypt's reputation, doctoring footage and aiding terrorists.

A fourth colleague – Abdullah Elshamy, a reporter for al-Jazeera's Arabic channel – has been jailed without charge in a separate case since last August. Fahmy recently celebrated his birthday in prison and has applied for permission to marry his fiancee inside jail.

In a handwritten letter smuggled from prison, Fahmy thanked the judges for the award and donated the prize money, worth C$2,000 (£1,100), to the family of an Egyptian journalist, Mayada Ashraf, who was shot dead in unexplained circumstances at a protest last month.

Fahmy wrote: "A key part of our defence has been to convince the judge of our professional integrity; to prove to him that we are journalists striving for the truth; and not agents of terror. This award will go a long way toward making our case."

Fahmy and his colleagues say the charges against them are absurd. In previous sessions, the prosecution's evidence has not appeared to include evidence of abetting terrorism or fabricated footage.

Instead, the video evidence has included footage of trotting horses, sheep farms and interviews with figures on all sides of Egypt's political spectrum that are comparable to work by most foreign journalists in Cairo.

The prosecution is expected to finish making its case in Saturday's session – which coincides with World Press Freedom day – while a verdict is expected at an eighth session due within a fortnight.

In court alongside the al-Jazeera trio are five students who have no connection to al-Jazeera, but who Fahmy claims have been added to the case to create the impression of an al-Jazeera-inspired conspiracy.

The students, Sohaib Saad, Khaled Mohamed, Shadi Ibrahim, Ahmed Ibrahim and Anas Beltagy, were arrested separately to the journalists and – according to a friend campaigning on their behalf – were initially told they would be charged in a separate case.

"When they were arrested, the police told us that they were going to be jailed for having maps of Egypt and planning to kill police officers," said Sara Mohamed, a friend of the five.

"It was only later that they were going to be involved in the AJ case. The boys started laughing out loud when they heard that."