The publisher of The Herald, Evening Times and Sunday Herald is to expand its printing plant to allow the titles to be published in full colour.

Newsquest Glasgow is investing £4m in new printing towers and other equipment that will also increase the capacity of its KBA Colora production line.

The plant currently prints more than 25 newspaper titles, with contract printing for the Daily Mail and Mail on Sunday as well as its own publications.

The existing press line is capable of producing 75,000 copies an hour, and once extention work is complete this will increase to up to 150,000 128-page full colour tabloid copies per hour.

Alistair Gay, production director at Newsquest Glasgow, said: "This investment will allow us to extend paginations and colour whilst maintaining the quality for which we are renowned."

Newsquest (Herald & Times) managing director Tim Blott added: "We are delighted to have finally concluded agreements with Associated Newspapers and KBA on this major expansion of our presses, securing the future of our Glasgow print plant for many years to come."

The extention is due to be completed in December.