"The aim of this brief is to provide a factual account of the incident during which fifteen Royal Naval personnel were seized by the Iranians last Friday. By way of background, HMS CORNWALL was in charge of the coalition force, which - alongside the Iraqi Navy - is operating in the Northern Persian Gulf.

"This force maintains the sovereignty and integrity of Iraqi territorial waters under UN Security Council Resolution 1723, and with the approval of the Iraqi Government. The ship – and others in the coalition - maintain a presence patrolling there. They are also charged with protection of the Iraqi offshore oil infrastructure – economically very important - and the security of merchant vessels.

"On 23 March a boarding team consisting of seven Royal Marines and eight sailors - who were embarked in two of HMS CORNWALL's boats - conducted a routine boarding of an Indian flagged Merchant Vessel which was cooperative throughout. They investigated this vessel after witnessing her unloading cars into two barges secured alongside. Since early March the force has conducted 66 routine boardings. So the one that I'm talking about was entirely routine business, and conducted in a particular area where four other boardings have been completed recently.

"As shown on the chart, the merchant vessel was 7.5 nautical miles south east of the Al Faw Peninsula and clearly in Iraqi territorial waters. Her master has confirmed that his vessel was anchored within Iraqi waters at the time of the arrest. The position was 29 degrees 50.36 minutes North 048 degrees 43.08 minutes East. This places her 1.7 nautical miles inside Iraqi territorial waters. This fact has been confirmed by the Iraqi Foreign Ministry.

"The Iranian government has provided us with two different positions for the incident. The first we received on Saturday and the second on Monday. As this map shows, the first of these points still lies within Iraqi territorial waters. We pointed this out to them on Sunday in diplomatic contacts.

"After we did this, they then provided a second set of coordinates that places the incident in Iranian waters over two nautical miles from the position given by HMS CORNWALL and confirmed by the merchant vessel. The two Iranian positions are just under a nautical mile apart – 1800 yards or so. It is hard to understand a reason for this change of coordinates. We unambiguously contest both the positions provided by the Iranians.

"I should just explain at this point that the boats remained connected at this point. One of the seaboats was connected via data link, which communicated its position continually to the ship where it was displayed, superimposed on an electronic chart, on a purpose built console. During the boarding this console was constantly monitored and indicated, throughout, that the boats had remained well within Iraqi territorial waters.

"Our boarding started at 0739 local time and was completed at 0910 with the merchant vessel having been cleared to continue with her business. Communications were lost with the boarding team as the boarding was finishing … at 0910. HMS CORNWALL's Lynx helicopter, which had been covering the initial stages of the boarding, immediately returned to the scene to locate the boarding team.

"The helicopter reported that the two seaboats were being escorted by Iranian Islamic Revolutionary Guard Navy vessels towards the Shatt 'Al Arab Waterway and were now inside Iranian territorial waters. Debriefing of the helicopter crew and a conversation with the master of the merchant ship both indicate that the boarding team were ambushed while disembarking from the merchant vessel. Both boats were equipped with a GPS chart plotter.

"On Sunday morning, 25 March, HMS CORNWALL's Lynx conducted an overflight of the merchant vessel, which was still at anchor, and once again confirmed her location on Global Positioning System equipment. Her Master confirmed that his vessel had remained at anchor since Friday, and was in Iraqi territorial waters.

"Ladies and Gentlemen, my primary message is clear. HMS CORNWALL with her boarding party was going about her legal business – in Iraqi Territorial waters, under a United Nations Security Council Resolution, with the explicit approval of the Iraqi government.

"The action by Iranian forces in arresting and detaining our people is unjustified and wrong. As such it is a matter of deep concern to us and the families of the people who have been taken. We continue not only to call for their safe, but for their safe and speedy, return, and we continue to seek immediate consular access to them as a prelude to their release."