Theresa May has embarked on a visit to the Middle East hoping to bolster links with the region post-Brexit.
During a three-day tour, Mrs May will hold talks in Saudi Arabia and Jordan, in a continuing effort to forge stronger ties with countries she visited earlier this year.
But the Prime Minister also intends to raise concerns about humanitarian issues and the Saudi blockade of Yemen.
Speaking to journalists on her journey to the Middle East, the Prime Minister said: “We are very concerned about the humanitarian situation in the Yemen.
“The UK is the third biggest bilateral donor of humanitarian aid to the Yemen.
“We are very clear that we want to see full humanitarian and commercial access through the port of Hodeida – and that’s obviously an issue I will be raising when I am in Saudi Arabia.”
The UK has been accused of being complicit in the Saudi air campaign by selling arms that have been used against Houthi rebels who are fighting President Abdrabbuh Mansour Hadi’s government.
Since the bombing of Yemen began in March 2015, more than £3.3bn worth of UK arms sales to Saudi Arabia have been licensed.
Mrs May has faced repeated calls to suspend arms sales following claims of breaches of international law by the Saudis.
More than 10,000 people have been killed and three million displaced during the two-and-a-half year conflict, while the Saudi-led air and naval blockade has driven millions more to the brink of famine.
However, Saudi Arabia is the UK’s largest trading partner in the Middle East and the Prime Minister sees it as a vital ally in the region.
She told journalists: “As the UK leaves the EU we want to forge a bold, confident future for ourselves in the world.
“But we need to look at the challenges that we and future generations will face and as we address those we need to ensure we are building stable partnerships to ensure our security.”
The Prime Minister added: “There’s no doubt in my mind that it’s in the UK’s national interests to work with Jordan and Saudi Arabia.”
While in Saudi Arabia, Mrs May will meet Crown Prince Mohammed bin Salman, who recently lifted the ban on women drivers.
As part of his social reforms, by 2030 the Crown Prince wants to increase the deeply conservative nation’s number of women in work and boost access to culture.
Mrs May said: “He is somebody who has a very clear vision of 2030 for Saudi Arabia.
“We’ve already seen some changes taking place in Saudi Arabia, for example women being allowed to drive.
“It’s important we work with him on delivering that vision.”
On Thursday, the Prime Minister will hold talks with Jordan’s King Abdullah II and Prime Minister Hani Al-Mulki on how Britain can support their long-term economic resilience.