Palestinian militant group Islamic Jihad released a video on Tuesday showing an Israeli hostage alive and held in the Gaza Strip.

The captive, identified by Israeli media as Sasha Trupanov, 28, is seen speaking in Hebrew in the 30-second clip.

Campaign group the Hostages and Missing Families Forum identified him as Alexsander (Sasha) Trupanov, and called on the Israeli authorities to secure the release of all captives held in Gaza.

It was unclear when the footage, in which he is seen wearing a T-shirt, was taken.

Trupanov, a Russian-Israeli dual national, was captured on October 7 from kibbutz Nir Oz along with his mother, grandmother and girlfriend.

The three women were freed during a truce between Hamas and Israel at the end of November, which led to the release of 105 hostages.

Trupanov's father was killed in the October 7 attack.

"The Israeli government must give a significant mandate to the negotiating team, which will be able to lead to a deal for the return of all the hostages -- the living to rehabilitation and the murdered to burial," a families' forum statement said after the release of Trupanov's video.

Israel's government has instructed its negotiating team to continue talks with mediators to secure a deal for the release of the hostages, but no new round of talks has begun.

The Gaza war was sparked by Hamas's October 7 attack on southern Israel, which resulted in the deaths of more than 1,170 people, mostly civilians, according to an AFP tally based on Israeli official figures.

Militants also took 252 hostages, 121 of whom remain in Gaza, including 37 the army says are dead.

Israel's retaliatory offensive has killed at least 36,096 people in Gaza, mostly civilians, according to the Hamas-run territory's health ministry.