London's top stocks look set to open about 20 points higher Tuesday morning after finishing in the red on Monday.Cable & Wireless Worldwide warns the coalition government's emergency budget will cause earnings growth to slow this year and come in at the lower end of the range of expectations. The largely UK focused part of the old Cable & Wireless, split off in March, said its major programmes and lines of business performed broadly in line with plan during the first quarter. But non-contracted spending in the UK public sector has slowed "very significantly", it cautioned. "Given the nature of our public sector business, this reduction will adversely impact trading in the current year."William Hill reported a rise in second quarter revenues, though gains from the World Cup were partly offset by a loss-making Royal Ascot festival. The group built on its improved performance in the first quarter, benefitting from strong growth in its online unit and gaming machines. For the year to date, net revenue was up about 3% compared with the same period in 2009 and pre-exceptional earnings before interest, tax and amortisation for the first half are expected to be around £135m from £134.6m last time.Tenanted pub group Enterprise Inns has continued to see an "improving trend" since the interim results on 11 May and predicts full-year results will match forecasts.Severn Trent's customers kept consumption steady over the past three months from April, while prices declined by 0.7%. As a result, the water utility has kept its expectations and guidance unchanged for this year.