The head of Yemen's Presidential Leadership Council, Rashad al-Alimi, on Tuesday declared a 90-day state of emergency as tensions escalated over control of southern Yemen and the influence of regional powers Saudi Arabia and the United Arab Emirates.
Al-Alimi, whose leadership is backed by Saudi Arabia, ordered the withdrawal of troops from the United Arab Emirates from Yemeni territory within 24 hours.
The UAE has been supporting a secessionist force in the south, called the Southern Transitional Council (STC).
According to Yemen's state news agency SABA, the decree by al-Alimi cancels a defence agreement between Yemen and the UAE, under which they had been fighting together against Iran-backed Houthi rebels in Yemen's years-long civil war.
Al-Alimi also announced a shutdown of all ports and border crossings across Yemen for 72 hours.
In a statement, the government backed al-Alimi's move and accused the STC of deploying weapons and forces outside official channels, constituting a serious security breach and a direct threat to citizens' safety.
The Saudi-backed council led by al-Alimi holds the reins of power in government-controlled areas of Yemen, but tensions have dramatically increased between the governing coalition and the STC in recent weeks.
Earlier this month, forces aligned to the STC took over large chunks of territory from the government in the provinces of Hadramaut and al-Mahra, which together make up around half of Yemen's territory.
Saudi forces early on Tuesday conducted a "limited airstrike" on two vessels in the southern Yemeni port city of Mukalla, saying they were delivering weapons to the STC.
The Saudi Foreign Ministry on Tuesday urged the UAE to withdraw its military forces from Yemen and halt all forms of military and financial support to what it called local actors.
It accused the UAE of exerting pressure on STC forces to initiate military operations near the Saudi southern border.
Riyadh warned that such actions threaten not only Saudi national security, but also Yemen's stability and the wider region.
Yemen expert and journalist Sadeq al-Wasabi described the developments on Tuesday as "an unprecedented military and political escalation."
"It was expected given the growing rifts between [Saudi Arabia] and the UAE over Yemen. Yemen will now enter a new phase of uncertainty," said al-Wasabi, who currently lives outside the country.
"All that is happening will only worsen the already disastrous economic and humanitarian situation in the country and will ultimately serve the Houthis' agenda," he said.
