The following is the text of the letter handed to the British ambassador in Tehran, according to IRNA, Iran's state news agency. "The Ministry of Foreign Affairs of the Islamic Republic of Iran presents its compliments to the British Embassy in Tehran and draws the attention of the latter to the following: According to the information received from relevant authorities of the Islamic Republic of Iran, two British naval vessels manned by 15 fully equipped crews trespassed on Iran's territorial waters on 3 Farvardin 1386 (23 March 2007). Since similar acts had taken place in the past and prior warning had been given against the repetition of such acts, the Government of the Islamic Republic of Iran protests strongly against this illegal act in violating Iranian territorial waters, emphasizes the respect for the rules and principles of international law concerning the sovereignty and territorial integrity of states, underlines the responsibility of the British Government for the consequences of such violation, and calls for the guarantee to avoid the recurrence of such acts. It will be appreciated if the esteemed embassy conveys this note to the relevant authorities of its government and informs this ministry of any explanation in this regard. The ministry of foreign affairs of the Islamic Republic of Iran avails itself of this opportunity to renew to the British Embassy the assurances of its highest considerations."