KABUL – President Hamid Karzai has issued a stinging rebuke to the US and the Taliban, saying they are both guilty of sowing fears for post-2014 Afghanistan.He said Taliban suicide attacks on Saturday were aimed at intimidation that would prolong the presence of international troops in Afghanistan.The troops are scheduled to end combat missions in 2014.Mr Karzai has cancelled a scheduled press conference with visiting US Defence Secretary Chuck Hagel.A senior Afghan presidential aide told the BBC this was because of tensions over civilian casualties, the handover of control of Bagram prison and the actions of US Special Forces in Wardak province.US officials said it was because of security concerns and not the president’s recent comments.In a nationally televised speech, President Karzai referred to two Taliban attacks on Saturday in Khost and Kabul that left 19 people dead.He suggested both the US and Taliban were trying to convince Afghans the situation would worsen after 2014.He said: "Yesterday’s bombings in the name of the Taliban were aimed at serving the foreigners and supporting the presence of the foreigners in Afghanistan and keeping them in Afghanistan by intimidating us.”Responding to Mr Karzai’s speech, US and Nato forces commander Gen Joseph Dunford said: "We have fought too hard over the past 12 years, we have shed too much blood over the last 12 years, to ever think that violence or instability would be to our advantage.”The BBC’s Quentin Sommerville in Kabul says relations between Mr Karzai and the US are in bad shape, with the president angry that the US has not transferred Afghan prisoners held in US custody at Bagram prison.The Afghan government also accused US-led forces and Afghans working with them of abusing and arresting university students, in violation of national sovereignty.Mr Karzai also said that "Taliban leaders and representatives are talking with the US abroad every day”.Our correspondent says the president would rather the insurgents spoke to him, but they will not do so as they regard his government as illegitimate. A statement from the US embassy in Kabul said Washington had "long supported an Afghan-led process for Afghans to talk to Afghans”.But it pointed out that the Taliban had suspended talks with the US in March 2012 and it was "up to the Taliban to take the next steps”.A Taliban spokesman denied the group was holding any dialogue with the US.Mr Karzai’s speech comes as Mr Hagel makes his first visit to AfghanistanAgencies.