The India Meteorological Department (IMD) on Sunday issued a cyclone alert for West Bengal and Bangladesh coasts after Cyclone Amphan intensified over the Bay of Bengal.

A deep depression in the ocean had intensified into the cyclonic storm last night and is likely to make landfall on the West Bengal coast on May 20. Its trajectory, however, is still being studied by the scientists.

Since last night, it has intensified slightly and is lying centred about 990 km south of Odisha's Paradip, 1140 km of south-southwest of West Bengal's Digha and 1260 km south-southwest of Bangladesh's Khepupara.

"Cyclone Alert for West Bengal and Bangladesh Coasts: Yellow Message," stated the weather department.

The cyclonic storm is very likely to intensify further into a severe cyclonic storm during the next six hours and into a very severe cyclonic storm during the subsequent 12 hours.

Pursuant to that, it is very likely to move nearly northwards during next 24 hours and then re-curve north-northeast wards across northwest Bay of Bengal and cross West Bengal-Bangladesh coasts between the Sagar Islands in West Bengal and the Hatiya Islands in Bangladesh during the afternoon or evening of May 20 as a very severe cyclonic storm.

The fishermen are advised not to venture into the south Bay of Bengal till May 17, to the central Bay of Bengal during May 17 and 18 and the North Bay of Bengal during May 19 and 20.

"Also, fishermen are advised not to venture into North Bay of Bengal along and off North Odisha, West Bengal and adjoining Bangladesh coasts during 18th to 20th May 2020," the weather department stated.

The NDRF, Armed Forces and the Indian Coast Guard have been put on alert and are coordinating with the state government authorities.