A military parade by Yemen's Houthi rebels in the key port city of Hodeidah on Thursday drew local and international condemnation from the UN, which regards the show of force as a breach of the 2018 agreement to demilitarise the city.
The UN Mission to support the Hodeidah Agreement (UNMHA) said it is "deeply concerned" by the Houthi moves.
The mission urged the group to "fully respect their obligations under the agreement, particularly as it pertains to keeping the city free of military manifestations".
Mohammad Al Basha, of the risk assessment group Navanti, said this was the largest military parade by the Houthis in Hodeidah.
"Parade showcased new water-borne improvised explosives, sea mines, drones, anti-ship missiles, rockets, SAMs, and much more," he wrote on Twitter.
Houthi-run Al Masirah television broadcast coverage of the military parade for more than an hour, along with speeches from military leaders praising the group's so-called resistance against their enemies.
Under the UN-brokered truce, fuel ships were allowed to enter the port of Hodeidah, providing much-needed reprieve to the people in terms of energy supplies and a source of revenue.
Hodeidah port is also vital for the flow of aid to the country. Yemen relies on food imports for 90 per cent of its wheat supply and all of its rice needs, according to figures from the World Food Programme.
The Houthis are also increasing activity in the besieged city of Taez, yet another sticking point between the warring sides in reaching a political settlement to end the war.
The UN and the Yemeni government have repeatedly called on the Houthis to end their siege of Taez by opening roads in and around the city to allow aid to flow through more freely and enable the population to move about.
Earlier this week, the Houthis launched an attack in Taez that killed 10 members of Yemen's armed forces.
Since then, Yemen's military says it has thwarted several attacks by the Houthis in Taez.
The UN truce will expire at the end of this month, but with the deadly Houthi attacks on Yemeni forces, it is unclear whether a third renewal will take place, especially after a military committee engaging in talks with the Houthis in the Jordanian capital said it is suspending ceasefire negotiations indefinitely.