With daytime testing of trams along Sydney’s CBD spine just weeks away, the tens of thousands of pedestrians who cross George Street every day are being warned they will need to take extra care.

While the trams will be travelling slowly during the initial testing phase, Transport Minister Andrew Constance said people needed to be aware that they took 15 metres to stop if they were travelling at just 20 to 30km/h.

Transport Minister Andrew Constance says pedestrians need to keep their wits about them. Credit:Brook Mitchell

"We just need people to be aware that ... [they] could get struck if they are mucking around on mobile phones," he said.

The allowable speed of the 67-metre trams through the CBD when the line opens to regular services in December has yet to be decided by regulators.