"This would be a one-time concession and thereafter, rules and regulations would be strictly implemented," the CM said at a public meeting at Vikas Nagar in the suburbs of Shimla.
The government had earlier introduced a bill in the Assembly and also promulgated an ordinance twice to regularise illegal constructions in Shimla, but it was withdrawn subsequently.
Singh said unauthorised constructions had mushroomed in various towns, including Shimla, adding that the situation poses a serious threat as the state falls in the seismic zone, highly prone to earthquakes.
The CM, also laid the foundation stone of a commercial complex of HIMUDA at Vikas Nagar, to be constructed at an estimated cost of Rs 62 crore.