LONDON – British Prime Minister Gordon Brown said Thursday he would move to block private groups from launching war crimes prosecutions against visiting foreign dignitaries, following a controversy inflamed when an arrest warrant was issued for former Israeli Foreign Minister Tzipi Livni. Brown said that Britain's principle of universal jurisdiction — a wide-ranging legal concept that allows judges to issue warrants for nearly any visitor accused of committing war crimes anywhere in the world — was being abused. While heads of state and senior ministers enjoy immunity, pro-Palestinian groups have used the law to try to arrest former or retired Israeli officials, including Livni, who now serves as opposition leader, and retired general Doron Almog, who narrowly dodged arrest at Britain's Heathrow Airport in 2005. Brown said the law was being abused by groups "who set out only to grab headlines knowing their case has no realistic chance of a successful prosecution." Writing in The Daily Telegraph Thursday, Brown said "Britain cannot afford to have its standing in the world compromised for the sake of tolerating such gestures." Israelis were outraged when an arrest warrant was issued for Livni in December ahead of her planned visit to the UK. The warrant was revoked after she canceled her trip, but Israeli officials said the opposition leader's treatment — and British arrest threats against other officials and military commanders — risked poisoning relations between the two countries. The Jewish state demanded that Britain change the law, which Israeli politicians described as absurd. Britain has previously invoked universal jurisdiction to arrest and prosecute Afghan warlord Faryadi Sarwar Zardad, who was convicted and jailed for 20 years on charges of torture and hostage taking.