US Democratic presidential contender Barack Obama has arrived in Afghanistan, at the start of a campaign-season international tour. Mr Obama flew to Kabul as part of a US congressional team. He is expected to meet Afghan President Hamid Karzai. He is later expected to visit Iraq, Jordan, Israel, Germany, France and Britain. Correspondents say Mr Obama is hoping to address security issues, seen as the weakest aspect of his presidential bid. Opinion polls suggest Americans regard Republican John McCain as a better potential commander-in-chief. In a speech earlier this week, Mr Obama said the US military should focus on Afghanistan rather than Iraq. There has been an upsurge in fighting in recent months between Taleban rebels and international and Afghan forces. Source: BBC