diageo to buy us wine firm diageo  the world s biggest spirits company  has agreed to buy californian wine company chalone for $260m (£134m) in an all-cash deal.  although diageo s best-known brands include smirnoff vodka and guinness stout  it already has a us winemaking arm - diageo chateau & estate wines. diageo said it expects to get us regulatory approval for the deal during the first quarter of 2005. it said chalone would be integrated into its existing us wine business.   the us wine market represents a growth opportunity for diageo  with favourable demographic and consumption trends   said diageo north america president ivan menezes. in july  diageo  which is listed on the london stock exchange  reported an annual turnover of £8.89bn  down from £9.28bn a year earlier. it blamed a weaker dollar for its lower turnover. in the year ending 31 december 2003  chalone reported revenues of $69.4m.