David Cameron arrived for talks in Saudi Arabia today as an influential group of MPs raised questions over British arms deals with the country.
The Prime Minister is meeting King Abdullah at his Riyadh palace for discussions that Downing Street hopes will "broaden and deepen" the UK-Saudi relationship.
Saudi Arabia is Britain's biggest trading partner in the Middle East with bilateral trade worth £15 billion a year and Saudi investment in the UK worth more than £62 billion.
But Mr Cameron's first visit to the nation since becoming premier came as the Committees on Arms Export Controls published details of questions it has raised with the Government over the licensing for a range of equipment.
Export permission was granted for bomb equipment, components for military combat vehicles and helicopters, weapon sights and communications technology.
MPs questioned why, given the unrest in Saudi Arabia early last year, licences had not been revoked as part of the Government's review of arms sales to the Middle East and North Africa.
They asked: "Why does the UK believe that the assurances relating to end-use will not be breached?"
The Government sees strong relations with the Saudis as vital to advancing Britain's interests in the region on a range of issues including energy security, counter-terrorism and political reform.
Meanwhile, Foreign Secretary William Hague has warned that Britain "must respect" the choices made by voters in countries that have ousted repressive regimes, even if they are considered extremist by the West.
In an article for The Times, he said: "It is true that parties drawing their inspiration from Islam have done better at the polls than secular parties and there are legitimate concerns about what this will mean.
"We must respect these choices while upholding our own principles of human rights and freedom and urging the highest standards.
"Trying to pick winners would fatally undermine faith in our intentions and our support for democracy. In standing up for the right of peoples to choose their own representatives at the ballot box, we have to accept their choices and work with the governments they elect."
As the Prime Minister met King Abdullah, reports emerged of clashes between protesters and security forces in the east of the desert kingdom which left one man dead.
Troops fired on demonstrators throwing rocks last night in the oil-rich Qatif province, according to Shiites.
The Interior Ministry said security forces returned fire after coming under attack when fleeing their patrol vehicle after it was hit by a firebomb.
Amnesty International called on Mr Cameron to be "completely frank and firm" with King Abdullah about human rights concerns in the country.
UK Campaigns Director Tim Hancock said: "There is shocking disrespect for basic human rights in Saudi Arabia and David Cameron should be completely frank and firm with King Abdullah about this.
"For example, he should bring up the case of six Bedouin men who face having their right hand and left foot amputated for 'highway robbery'. The men had no lawyers at their trial and one of them was reportedly beaten for eight days to make him 'confess'.
"In Saudi Arabia women are treated as second-class citizens. They can be flogged if they're caught driving a car and they have to receive the permission of a male guardian before they can travel, start a job or get married.
"If Samantha Cameron were on this visit she would be unable to drive or move around freely without risk of arrest.
"In recent years we've documented the indiscriminate bombing of Yemeni villages by Saudi Arabian jets, so if Mr Cameron is discussing arms deals on this trip he must ensure that they will be subject to rigorous controls and that no equipment is shipped to the country if there is the slightest risk of it being used to commit human rights abuses."
Downing Street said Mr Cameron and King Abdullah had agreed to "strengthen cooperation" between their two countries.
They also spoke about unrest in the wider region and piracy and lawlessness in Somalia.
A Downing Street spokesman said: "They discussed the importance of the UK-Saudi bilateral relationship and agreed to strengthen co-operation in a range of areas.
"The two leaders also discussed recent developments in the region, in particular their shared concerns about the situation in Syria, Iran and Yemen.
"The Prime Minister also raised our concerns about Somalia and the problems of conflict, piracy and terrorism which threaten Somalis and the wider international community.
"He briefed the king on the aims of next month's London conference on Somalia, in particular to catalyse a co-ordinated international effort focused on practical measures to help Somalis rebuild their country."