London: Britain is reportedly drawing up a battle plan for a war with Iran as top defence officials believe London will be "sucked into" any new conflict with Tehran.
Plans are being made to send hundreds of troops and an nuclear submarine to the Gulf region, The Sun reported.
Defence officials believe it is just a matter of when the war breaks out -- with the timescale set between 18 and 24 months.
"Ministry of defence planners went into overdrive at the start of the year. Conflict is seen as inevitable as long as the regime pursue their nuclear ambitions. Britain would be sucked in whether we like it or not, probably via Iranian attacks on our forces in Afghanistan next door to them," an unnamed official said.
The report said Britain will first fly an infantry battalion to the United Arab Emirates (UAE), the country`s strong ally in the Gulf region.
It would also mean a "public show of support" that would demonstrate that Britain was ready to defend the UAE if it comes under attack from Iran.
The UAE is separated from Iran by just over 50 km of sea across the Strait of Hormuz.
If other allies like Oman, Kuwait, Saudi Arabia, Bahrain and Qatar ask for help, Britain could fly in further troops.
The Royal Navy has already gathered seven warships in the Gulf.
The HMS Daring, a powerful destroyer, arrived in January to join Type 23 frigate HMS Argyll.
Minesweepers Pembroke, Quora, Middleton and Ramsey are based in Bahrain and a nuclear submarine is reportedly also in the area, the report said.
Under the war plan, a second submarine armed with Tomahawk cruise missiles would be deployed.
The Royal Air Force would send Typhoon and Tornado fighter jets to reinforce helicopter and transport plane crews already stationed in Qatar, Oman, Bahrain and the UAE.