BRITISH RAIL has unveiled its latest excuse for summer.

With 'leaves on the line' and the 'wrong kind kind of snow' now unlikely to fool customers, the worst threat so far has been uncovered.

"Pollen on the line is a problem which we expect to cause major delays," BR spokesman Laurie Locomotive told DMTV News. "The reason is that pollen settling on the tracks causes a tremendous amount of slippage - so much so that we expect to have to run trains at no more than 20 miles per hour."

Asked if anything was to be done to tackle the pollen problem, Locomotive replied, "What?! And lose our latest lame excuse?!"