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(Updates with GCC-British communique, previous LONDON)
DUBAI, Dec 7 (Reuters) - Britain plans to deepen securitycooperation with Gulf Arab countries and work with them tocounter Iranian actions in the region, Prime Minister TheresaMay said on Wednesday.
Addressing a meeting on the sidelines of the GulfCooperation Summit in Bahrain, May said Britain would investmore than 3 billion pounds in defence spending in the regionover the next decade.
"Gulf security is our security," May said.
Britain is trying to build on traditionally strong ties with conservative, oil-wealthy Gulf Arab monarchies before itsplanned departure from the European Union.
In a joint communique, the two sides said they intended tobuild on trade between Britain and the Gulf Cooperation Council(GCC) states, which stood at 30 billion pounds in 2015.
"We will make it a priority, when the UK leaves the EuropeanUnion, to build the closest possible commercial and economicrelationship," the statement said.
This included working to remove barriers to trade andinvestment.
The joint communique also said the GCC states and Britainwould work together to counter what they called "Iran'sdestabilising activities".
Gulf Arab states say Iran is trying to expand its influencein Arab countries, including Syria and Yemen. Since March lastyear, Saudi Arabia and other Arab allies have been fighting awar against Iran-aligned Houthi forces that had seized controlof Yemen.
The two sides also pledged to enhance defence cooperation, including efforts to defeat Islamic State and in maritime andcyber security through their new Strategic Partnership.
The statement stressed that regional conflicts can only beresolved through diplomacy.
Prior to the visit, Britain's close relationship with the Gulf States drew concern from human rights groups, includingcriticism of Saudi air strikes in Yemen which have killedhundreds of civilians. British military personnel have beeninvolved with the Saudi forces.
Human Rights Watch and other organisations sent a jointletter to May urging her not ignore rights issues in pursuit oflucrative business deals. They also highlighted a politicalcrackdown in Bahrain, where Britain has recently opened a navalbase.
Asked by a reporter aboard the British warship Ocean inBahrain on Tuesday whether Britain was selling its principlesfor profits by engaging politically with Gulf Arab states andselling them weapons, May said: "No. What is important is thatwe are able to raise these human rights issues with Gulf Statesand with other states around the world."
"In order to be able to do that we need to engage with thosestates," May said. (Reporting by Elizabeth Piper in London and Sami Aboudi andNoah Browning in Dubai, Editing by Angus MacSwan)