Secret plans to run down domestic coal industry were being drawn up even before the year-long miners' strike had ended

Secret plans to run down the domestic coal industry and defeat any future strike action by unions were being drawn up by Margaret Thatcher even before the year-long miners' strike had ended, cabinet papers reveal.

The plans were approved by a group of inner-circle ministers in September 1985 ‑ five months after the strike ended. They sealed the fate of the British coal industry and were rigorously followed by successive Conservative governments. Under the plans, ministers agreed to keep a permanent stockpile of at least six months' supply of coal, increase coal imports, build more oil-burn, nuclear and gas-fired power stations and encourage development of more opencast mines.

They also agreed to a deal with the French to supply power stations with electricity by doubling the size of the cable connecting the two countries, and to switch coal deliveries to power stations from rail to road to prevent the unions from disrupting deliveries.

Other parts of the plan included changing the law so that rioters could be more easily prosecuted, and cutting state help with mortgage interest payments for home owners on benefits. The latter was to ensure that strikers with homes could face repossession, but was not to be officially acknowledged as part of any anti-strike plan.

Ministers also sanctioned an overhaul of internal communications between management and workers in nationalised industries. In addition, they agreed to the appointment of a more media-savvy public spokesman for the coal, steel, water and railway industries then in state control.

A cabinet paper admitted that Arthur Scargill, the miners' leader, had outgunned the government with his handling of the media during the dispute.

"The NUM used the media with considerable skill and to good effect, due in large measure to Scargill's personal fluency and energy," it said.