David Cameron, UK prime minister, has sought to balance British concern over human rights in Gulf Arab states with winning lucrative arms deals for his country as he started a tour of the region.Cameron said on Monday that supported calls for greater democracy in the Middle East and that the British government was engaging Gulf states - some of which are facing political unrest - on their human rights record.But discussions would show "respect and friendship”, he said, recognising that governments have bridled at foreign criticism.Cameron arrived in the United Arab Emirates on Monday and will visit Saudi Arabia on Tuesday before travelling to another destination in the Middle East.High on his agenda will be selling the BAE Systems-built Eurofighter Typhoon fighter jet.BAE officials say the UAE has shown interest in ordering up to 60 Typhoons. He will also talk to UAE officials about how to develop a "strategic air defence relationship”, including collaboration on military aerospace equipment.Saudi Arabia has also signalled it might place a second substantial order of Typhoons on top of the 72 jets it has already acquired, Cameron’s office said.However, Cameron’s trip is complicated by human rights issues as Gulf states struggle to contain protests inspired by the Arab Spring and Western nations weigh up their own strategic and commercial interests.Saudi Arabia and the UAE have both bridled at criticism by the British parliament, media and human rights groups over their alleged lack of democracy and stifling of dissent.Cameron himself has also been taken to task at home for muting criticism of pro-Western Gulf states - and trying to sell them arms - in comparison to his strident support for the opposition in other Arab struggles such as Libya and Syria.