Iran is calling on other nations not to interfere in Yemen's affairs, as Saudi Arabia continues a cross-border offensive against Yemeni rebels.
Iran's state-run Press TV news agency quoted Foreign Minister Manouchehr Mottaki as saying all countries must respect Yemen's territorial integrity.
Saudi forces began an offensive last month in northern Yemen against rebels of the Shi'ite Zaidi sect after the rebels killed two Saudi guards in a cross-border attack. Predominantly Shi'ite Iran has criticized Sunni-majority Saudi Arabia for entering the conflict.
Yemen's government has been fighting the rebels, also known as Houthis, for years and accuses Iran of backing them. Shi'ite Zaidis accuse Sanaa of denying them civil, economic and religious rights.
In another development, Yemeni authorities arrested 40 motorcyclists Wednesday in the country's south for taking part in anti-government protests.
Officials say the protesters were detained in the southern region of Lahj. They say the motorcyclists were demonstrating against new rules imposed on them by Yemen's northern-based government, including requirements to number their vehicles and obtain driving licenses.
Yemeni media say several people were injured in fighting between separatist protesters and security forces in the region.
Separatist sentiment is strong in southern Yemen, where many residents accuse the central government in the north of discriminating against them. Anti-government activists in the south have been waging a campaign to undo the region's 1990 unification with the north.
Some information for this report provided by AP, AFP or Reuters.