The launch of US supermarket Safeway Inc's online shopping service powered by Tesco.com has been delayed by technical problems. The service was supposed to be up and running before Christmas after a series of pilots in California resolved any outstanding technical issues. The launch date has since been extended to "some time during the first quarter," said a spokeswoman. Tesco.com chief executive John Browett insisted things were progressing according to plan. He was not able to give a date for the launch of the service in South Korea, where Tesco is also keen to develop the service. Central European markets, where Tesco also has a presence, are not suitable for the service, as internet penetration is very low, he added. "We are really focusing on the US at the moment." {{NEWS }}