A UAE-trained militia said on Saturday some of its fighters remained on the front lines in key Yemeni conflict zones as part of defensive measures after driving out the Houthi rebels.

The Giants Brigades said on Friday it had begun repositioning its forces after pushing the rebels back from oil-rich Shabwa province and stopping short of launching a northward offensive towards the strategically vital city of Marib.

The surprise announcement followed two drone and missile attacks by the Houthis on the UAE, the first of which killed three oil workers.

Having lost ground to the Emirati-trained forces, the Houthis have warned of further attacks on the UAE unless such operations are halted.

The wealthy Gulf state pulled out of Yemen in 2019 but remains an influential player in a Saudi-led coalition supporting the internationally recognised government against the Iran-backed rebels.

“The forces completed their mission in liberating the district of Shabwa and securing it and pushed the Houthis out of the district of Harib, south of Marib,” a Giants Brigades official, who spoke on condition of anonymity, told AFP.

“The force that was repositioned did not leave the front lines, but rather began putting up defensive measures to repel any military attacks by the Houthis," he said. “What is not yet liberated in the Marib [province] is left up to the government which has hundreds of thousands of soldiers, and it is their turn to kick out the Houthis from Marib.”

Read: Wars on many fronts

The Houthis and pro-government troops have been engaged in months-long battles in the south, north and west of the Marib city, the government's last northern holdout.

The Giants Brigades, fighting as part of the Saudi-led pro-government coalition, dealt a serious blow to the Houthi campaign after moving into Shabwa.

After their defeats in Shabwa, the rebels seized a UAE-flagged ship on January 3 before launching a deadly strike on Abu Dhabi on January 17. A second strike a week later was intercepted.

An Emirati official said on Thursday that Houthi attacks would not become a “new normal” for the UAE, vowing a robust defence.

“This is not going to be the new normal for the UAE,” the official told AFP on condition of anonymity.“The UAE has world class defence capabilities and is constantly seeking to update them.”

The Yemen conflict, which erupted in 2014, has killed hundreds of thousands of people directly or indirectly and left millions on the brink of famine, according to the UN.