Estate agent Savills reported strong trading at its UK residential and Asia Pacific businesses but said its European arm continues to face difficult conditions.The UK residential business has continued to perform strongly since June driven by London and the South East, though Savills remains cautious given the prospect of a general election and increased taxation in the second quarter of 2010.In the commercial arm, the firm's UK investment has been focused on long-lease properties in exclusive areas that are able to rely on demand from occupants from around the world. While there has been minimal investment beyond this area the firm says there are some recent signs that 'investors are starting to look at the next tier down.'Hong Kong and China have helped drive business forward in the Asia Pacific region, Savills said.Overall, continental Europe has seen little investment activity in the commercial property although recently there has been an increase in investor interest in markets such as Paris, Savills said. The Irish business has continued to be adversely affected by the tough economic conditions there.