The West Bengal government is yet to work out a plan to clear the dues. "We have given them (Bihar and West Bengal) one-month notice to clear dues by March failing which NTPC would start regulation of power supply in these two states," executive director commercials, NTPC, H L Bajaj told PTI.

Bihar has to pay about Rs 2,209 crore (including surcharge) while West Bengal owes the corporation Rs 1,188 crore till January-end (provisional), Bajaj said.

The letter of credit (LC) extended by Bihar is also not workable because as against the LC of Rs 75 crore, NTPC is able to cash only Rs 25 crore posing problem for the company's future power projects.

Power availability to the two states would be made only to the extent of the LCs available, he said.

NTPC's dues till January-end (provisional) have touched an all-time high of about Rs 12,200 crore, he said adding that the company was supplying 900 mw of power to Bihar while West Bengal was drawing about 700 mw of power from the corporation.

Bajaj said that NTPC had last month taken over the 440 mw of power plant of Uttar Pradesh State Electricity board (UPSEB) Tanda thermal power plant to adjust against the dues. NTPC had taken over the Tanda plant to adjust the dues to the tune of Rs 1,000 crore. The dues of Uttar Pradesh till January-end (provisional) now stands at Rs 1747 crore, Bajaj said.

UPSEB had assured in April 1999 that they would enhance their LCs and make regular payments when disconnection notices were issued to them then, he said adding that during December as against the bill of Rs 1586 crore the electricity board had made payments to the tune of Rs 861 crore.

The corporation was also planning to mop up Rs 50 crore from UPSEB through issue of bonds and discussions in this regard to this were on, Bajaj said.Asked about the dues owed by Delhi, Bajaj said that the Delhi Vidyut Board had started to make regular payments of Rs 130 crore every month.

He, however, said that the dues of the state had touched Rs 2,328 crore. Company sources said that NTPC was facing serious problems due to the mounting arrears from various SEBs as it was also affecting the corporation's future power generating projects.