An unprecedented water crisis loomed large over the national capital on Thursday with neighbouring Haryana drastically cutting supply, leaving various treatment plants short of raw water and areas across Delhi parched.

Top officials in the Delhi Government said most areas in the city will face severe water shortage and accused the neighbouring state of playing "foul" with Delhi on the water issue.

Considering the gravity of the situation, Chief Minister Sheila Dikshit has been trying to speak to her Haryana counterpart Bhupinder Singh Hooda but to no avail, sources said.

"It is expected that around 25 lakh residents in Khayala, Patel Nagar, Moti Nagar, Kirti Nagar, Narela, Bawana Wazirabad, and old Delhi localities will be severely affected," the statement from Dikshit's office said.