<br/> Cambodia today rejected Thailand's request to extradite Thaksin Shinawatra, inflaming tensions over Phnom Penh's appointment of the fugitive former Thai premier as an economic adviser. Billionaire Thaksin, who was toppled in a bloodless coup in 2006 and lives abroad to avoid a jail term for corruption, arrived in Cambodia yesterday and received a warm welcome from Cambodian Prime Minister Hun Sen. Cambodia had repeatedly vowed to refuse any request from Thailand for the extradition of Thaksin, saying that the charges leveled against him were politically motivated. <br/><br/> Tensions are already running high between the two countries following a series of clashes over a temple on their border and the row threatens to mar a weekend summit of Southeast Asian leaders with US President Barack Obama.