Al-Jazeera satellite news channel has called on Israel to release its former Kabul bureau chief ahead of the journalist's appearance before a court on Wednesday.
Samer Allawi, a Palestinian, was detained on August 10 by Israeli security officials as he tried to cross the border between Jordan and the West Bank after a family visit.
An Israeli military court in the northern West Bank has accused Allawi of being a member of Hamas and of having "contacts" with the military wing of the Islamist movement, which rules Gaza.
Al-Jazeera, which is based in Doha, Qatar, appealed for Allawi's release in a statement on Tuesday.
"Samer has already been held for an unacceptable period of time," he said. "His family are understandably worried about him... We call upon the Israeli authorities to release him at tomorrow's hearing."
According to the statement, Israeli authorities used Allawi's personal passwords to gain access to Al-Jazeera's internal news and email networks.
Allawi, who was also captured by the Taliban while on assignment in Afghanistan, is one of several Al-Jazeera journalists to have been detained in the past few months in Egypt, Libya, Syria, and Iran, the statement said.
Relations between Israel and Qatar have soured considerably in recent years, particularly since the Jewish state's massive 22-day military assault on the Gaza Strip in December 2008 and January 2009.