Yemen is doing all that it can to secure the release of an Iranian diplomat kidnapped in Sanaa last month, said Foreign Minister Abu Bakr al-Kurbi.

The authorities were "exerting all efforts" to free the official, Kurbi was quoted as saying by state news agency Saba after holding talks late Tuesday with an Iranian foreign ministry delegation in the Yemeni capital.

Nour-Ahmad Nikbakht, identified by Tehran as an administrative staff member of the Iranian embassy in Yemen, was abducted on July 21.

Tribal and security sources have told AFP that "Al-Qaeda militants" are holding him hostage in a remote region between the provinces of Shabwa and Bayda in the country's south.

The militants have also been holding a South African couple hostage since May, along with a Dutch couple kidnapped in June, according to these sources.

The Dutch pair have issued an impassioned plea in an Internet video for their government to act to secure their release, warning they face execution.

The kidnappers are demanding the release of their prisoners in Yemen or a ransom, tribal and security sources said.

Hundreds of people have been abducted in Yemen in the past 15 years, nearly all of them later freed unharmed.

Kidnappings are often carried out by tribesmen who use their captors as bargaining chips in disputes with the central government.

But recently, militants of Al-Qaeda in the Arabian Peninsula (AQAP), who remain in their hideouts in the impoverished country's south and east, have been seizing foreign hostages.

AQAP militants are still holding Saudi Arabia's deputy consul in Aden, Abdullah al-Khalidi, whom they seized in March 2012.

They are demanding the release of female Al-Qaeda-linked prisoners held in Saudi Arabia in return for Khalidi's release.