The railways has allowed work on laying the foundation of only one of the four pillars of the Tallah bridge that will come up between railway tracks.

The PWD, which is executing the Rs 340-crore bridge project, had sought permission for all four pillars and traffic block on the tracks to facilitate work.

Railway officials have said that if work on all four pillars starts simultaneously, movement of all types of trains will have to be suspended for 30 days.

“A traffic block for a prolonged period would mean disrupting movement of trains in different directions,” a railway official said.

PWD officials said on Monday the decision of the railways to withhold permission for the other three pillars might affect the pace of work.