The directors of a company make decisions about whether or not to pay dividends to shareholders. The government does not have powers to interfere in the conduct of a PLC, other than by legislation.
As for "most large shareholders are large commercial enterprises themselves, who main aim in life is making profit"
Well of course they're interested in making profits - they want to attract and keep their own shareholders. I would have though you would understand that.
Under the terms of the Companies Act 2006 all company directors have an over-arching duty to act in the way they consider, in good faith, would be most likely to promote the success of the company.