Venues include Downton Abbey's Highclere Castle, Englefield House, Sheepdrove Eco Conference Centre and the chapel at Andrew Lloyd Webber's Sydmonton Court home. The festival will run from Saturday, May 11 to Saturday, May 25.
Holly Payton-Lombardo, marketing manager, said: "The festival is gearing up for May 2013, with an exciting new line-up! With plans falling into place we are delighted to announce this year's international programme.
"We celebrate the bi-centenaries of Wagner and Verdi, and the centenary of Britten, arguably the greatest opera composers of the 19th and 20th centuries.
"We also continue our focus on outstanding young musicians from home and abroad, and this year feature the piano in more guises than ever. So get ready for two weeks of world class music making, 45 events in a dozen locations in Newbury and its surrounding area of outstanding natural beauty."
The international section of the festival is centred on a Russian theme and will feature the Moscow State Symphony Orchestra, the Borodin String Quartet and introduce rising young soprano Gulnara Shafigullina.
Some of the UK's best loved musicians will also appear, including the evergreen Black Dyke Band and Britain's favourite London Community Gospel Choir.
The event will also play host to the 2006 BBC Young Musician of the Year and BBC Proms and Guardian Young Composer of the Year, Mark Simpson, whose new works will be performed by Christ Church Cathedral Choir at Douai Abbey in Upper Woolhampton on the last night.
Tickets are now on sale, and prices range from £12-£38 depending on the venue.
Visit www.newburyspringfestival.org.uk or call 0845 521 8218.