By Mohammed Ghobari
Nov 15 (Reuters) - Iran and its allies ramped up pressure on the US and allied Gulf states on two fronts on Sunday, with Saudi-backed forces retreating in their battle against the Iran-aligned Houthis in Yemen and Iran itself firing drones at US bases in Bahrain.
In Yemen, Saudi Arabia's campaign against the Houthis suffered a major setback, as its allies, fighting on behalf of the internationally recognised Yemeni government, pulled back from the Bab el-Mandeb Strait to defend
their temporary capital Aden on the southern coast.
The announcement signalled the apparent end of a six-week government counteroffensive to drive the Houthis from the mouth of the Red Sea to secure a key oil route.
Meanwhile, Iranian attacks on Bahrain, headquarters of the US Fifth Fleet in the Gulf, were likely to put new pressure on US President Donald Trump to resolve the war he launched nearly nine months ago.
Since the unpopular war contributed to a defeat for his Republicans in midterm elections this month, Trump has played down the need for a diplomatic breakthrough.
Major warfare between the US and Iran has calmed since the early phase of the conflict, but with diplomacy stalled there is little immediate prospect of a resolution either to the wider conflict or the war in Yemen.
HOUTHI GAINS
Sunday's announcement of a Yemeni government retreat raises the prospect of new Houthi advances towards Aden on the southern coast, base of the internationally recognised government since the Houthis drove it from the capital Sanaa more than a decade ago.
"The Southern Armed Forces announce the implementation of a redeployment operation for its forces from Dhubab Airport and the Bab el-Mandeb area, west of Taiz Governorate," the main military force fighting for Yemen's government in the south of the country said in a statement.
"This step is taken based on the priority of securing the capital, Aden, and the neighbouring governorates, as well as strengthening the front lines and addressing existing threats."
There was no immediate response from the Houthis, or from Saudi Arabia.
The retreat signals a setback for efforts to reverse rapid gains the Houthis made in September to capture the coast along the Red Sea and the Bab el-Mandeb Strait that controls access to it.
A Saudi-backed government offensive last month retook key positions around the strait but failed to drive the Houthis entirely away from the area or retake the city of al-Mocha further up the coast.
The Houthis have responded by intensifying drone and missile attacks on Saudi Arabia, grounding flights with strikes on its main airports as well as setting global oil markets on edge by targeting energy facilities.
Yemeni military sources said that government forces around the Bab el-Mandeb had redeployed to al-Suqyah, 150 km (95 miles) west of Aden, though they were still trying to push the Houthis from coastal areas nearby.
In the highlands north of Aden, where the Houthis have besieged Yemen's third-largest city Taiz, the fighters are now positioned just outside the district of Tur al-Bahah, about 80 km (50 miles) from the city, the sources said.
Humanitarian conditions are worsening in Taiz, which hosts about half of the 300,000 people displaced across Yemen by the latest fighting. Aid supplies are unable to enter and civilians are unable to leave.
IRANIAN STRIKES ON BAHRAIN
Fresh Iranian strikes on Bahrain, home to US bases, could undermine Trump's desire to turn the page on the war following his Republicans' midterm election rout.
Trump has said in recent days that he might hold off from attacking Iran if the US faces no new provocations from either Tehran or the Houthis in Yemen, although he would maintain a US naval blockade on Iran, Reuters reported on Saturday.
Bahrain said it intercepted and destroyed several Iranian aerial attacks, the first such interceptions by its air defences since September.
Iran's Islamic Revolutionary Guard Corps said it had attacked a US military base in Bahrain with six drones in retaliation for "hostile US actions", Iran's Fars news agency reported.
During a brief alert, Bahrain urged citizens and residents to remain calm and proceed to the nearest safe location.
Two days earlier the Revolutionary Guards said they had attacked a US early-warning radar facility in Bahrain. The US military denied this, saying it had intercepted two Iranian drones without any damage.
Crude oil has been flowing out of the Gulf in recent weeks at near pre-war levels. But attacks on ships have become a daily hazard, keeping markets jittery and prices still elevated.
The Revolutionary Guards said two tankers were on fire on Sunday after striking naval mines in the Strait of Hormuz. Reuters could not independently verify the report. The Guards typically do not acknowledge attacking ships in the strait but say it is unsafe to transit it without their permission.
Iran's Foreign Minister Abbas Araqchi will on Tuesday visit Oman, which holds the southern coast of the Strait of Hormuz and has played a role as mediator in the crisis, for talks with his counterpart, Iranian state media reported.
(Reporting by Mohammed Ghobari; Additional reporting by Reyam Mukhashaf in Aden; Writing by Nayera Abdallah and Angus McDowall; Editing by Peter Graff)
