In May 2010, Trimble joined the Friends of Israel Initiative, a non-Jewish international project supporting Israel's right to exist. The initiative, started by former prime minister of Spain José María Aznar, also included former United States Ambassador to the United Nations John R. Bolton, British historian Andrew Roberts, and former Peruvian president Alejandro Toledo. On 29 January 2013, Trimble and Aznar co-wrote an article in "The Times" condemning Hezbollah and calling on European governments to list it as a terrorist organisation.