DOWNING Street has held out the prospect of new legislation to curb what it regards as intimidatory tactics by the Unite union as Labour continued to hold the line on the Falkirk selection controversy despite the release of a revelatory leaked email.

Len McCluskey, Unite's General Secretary, made clear his union would continue with its so-called "leverage" campaign, highlighted during the row over the Ineos-owned Grangemouth petrochemical plant.

The union baron, complaining of "unscrupulous smears" by MPs and the media, said the strategy's purpose was to tell "bad bosses they have nowhere to hide". He said: "The silent peaceful protests in the leafy suburbs of a few directors are part of our basic human rights, which include freedom of expression."

Asked if the UK Government was looking at legislation to curb such behaviour, the Prime Minister's spokesman said: "We are in the process of considering whether or not there is something to be done in this area."

Meantime, Labour leader Ed Miliband's office said it was awaiting the outcome of police inquiries to see if it should reopen its own probe into the Falkirk selection row. Ex-Chancellor Alistair Darling says it should.

Police Scotland is examining emails supposedly from Unite official Stephen Deans to see if they merit a full criminal investigation. Mr Deans resigned his position at Grangemouth in the wake of an Ineos inquiry into claims he used company time to do work for Labour.