The move follows the controversial takeover of confectioner Cadbury by the American food giant Kraft.
The government said it was powerless to stop the deal, but will now propose that two-thirds of shareholders will have to vote yes to some takeovers.
Labour is refused to confirm or deny the manifesto leak to the BBC or other media outlets.
Labour’s manifesto is understood to contain proposals to ensure that if a company is designated “strategic”, or if the national interest is concerned, two-thirds of its shareholders will have to vote yes to a takeover.
Under the current law, a straight majority will suffice.
In addition, there will be rules to stop hedge funds buying up shares.
These plans are designed to stop speculators making a quick profit on a takeover. Under the proposals, only long-term investors will have a say in whether a company is sold.
The campaign for the so-called Cadbury’s law has been led by the Unite union,who are the Labour parties largest donors, but has gained popularity among those unhappy at the way in which the confectioner was bought out by Kraft.
Some observers felt Kraft should have paid more for Cadbury, and that short-term investors pushed through the deal.
The Liberal Demcrats have already called for such a law.
