FLIGHTS to and from the US have been hit by delays as the volcanic ash cloud continues to spread south from Iceland. Transatlantic travel time has been extended by one to two hours as jets have to divert around the 1,200mile-long cloud. Delays are expected to continue for at least 24 hours. Air traffic management agency Eurocontrol said the cloud above the Atlantic has lifted to 35,000ft - jets' cruising height. This means planes can no longer fly above the plume from Iceland's Eyjafjallajokull volcano.