Britain is bracing itself for a national docks strike next Tuesday which would shut down 80 ports and paralyse the country's vital overseas trade.

With only three days to go before the dockers scheduled walk-out, exporters and importers have been rushing to beat Tuesday's deadline.

The strike call -- over a pay dispute -- would bring out the nation's 47,000 dockers for the first since the General Strike of 1926 -- 44 years ago.

The new Conservative Government of Prime Minister Edward Heath stepped in early to mediate in the dispute. Both sides are meeting with government officials over the weekend in a last minute bid to find a solution.

If they are unsuccessful, the strike would cripple Britain's export trade and jeopardize the country's balance of payments.

Meanwhile, the Government is making emergency plans to bring in troops to move essential cargoes although it has stressed that this action would be a last resort.

The last major shipping strike -- involving merchant seamen -- lasted nearly seven weeks and cost the country millions of pounds.