Yemen's human rights minister says heavy fighting is underway in the country's south as rebel Houthis push to gain more territory from government forces and their allies.

The clashes come as the Saudi-led coalition carried out airstrikes on the capital, Sanaa, earlier on Thursday, targeting the Houthis and killing at least three civilians.

The strikes were in apparent retaliation for a drone attack on a Saudi pipeline earlier this week that was claimed by the Iran-aligned rebels.

The Yemeni minister, Mohammed Askar, told reports that weeks-long fighting in the southern governorate of Dhale has killed over 27 civilians and displaced around 10,000 people.

Yemen has been embroiled in a civil war pitting the Houthis against the government of President Abed Rabbo Mansour Hadi, backed by the coalition, since March 2015.