Smartphone giant Samsung has reported that it has offered to buy out its struggling rival BlackBerry for around $7.5 billion (£4.92 billion) as it saw the firm’s shares rise 30% in US trade.

In an email BlackBerry said it was "aware of certain press reports" about an offer from Samsung but confirmed it had "not engaged in discussions with Samsung with respect to any possible offer to purchase".

It was reported that in December BlackBerry’s revenue had fallen to $793 million (£507 million) from $1.9 billion the year before which chief executive John Chen of the firm at this time said the revenue figure was "not satisfying".