UPDATE 1-India's monsoon stays weak as govt mulls drought steps

* Weather office's next forecast early next week

* Drought panel may approve more diesel funds for farmers

* For latest weekly crop planting data (Adds details, background)

NEW DELHI, July 27 (Reuters) - India's monsoon rains are unlikely to pick up enough to avert the possibility that ministers meeting next week may officially declare a drought, which could prompt the government to offer more support for farmers to ensure adequate food supplies.

Rains from June 1 up to the end of the planting month of July are likely to be 21-22 percent below average, Farm Secretary Ashish Bahuguna said on Friday, unchanged from the seasonal shortfall recorded up to July 25.

India's crucial June-September monsoon rains were 29 percent below average in the first month of the season, while the rains were about 15 percent below average so far in July.

India's government raised the possibility of a drought for the first time on Thursday when Farm Minister Sharad Pawar said ministers would meet early next week to discuss the situation. Over half of India's farmlands are rain-fed.

India's Meteorological Department (IMD) is likely to revise its official forecast of average rains early next week after the government said rainfalls were now expected to be below average at around 92 percent of usual levels for the entire June to September season.

Levels below 90 percent are officially viewed as "deficient" -- a drought in layman's terms.

The IMD's latest weekly outlook, issued on Friday, suggested rains would continue to be patchy next week, picking up in northern areas during the second half but decreasing in central and east India.

The four-month monsoon brings 75 percent of annual rainfall and half of that is usually delivered in June and July, when India's farmers plant most of their summer-sown crops.

The crisis for one of the world's largest consumers and producers of commodities including sugar, rice, cereals, oilseeds and pulses comes as global prices for cereals reach record highs on a major drought in the United States.

Bahuguna said the rains have led to lower acreage planted with pulses and oilseeds, echoing the concerns of Food Minister K.V. Thomas. India is a major importer of pulses and edible oils and any increase in purchases could fuel already high inflation.

The government has launched contingency plans to ensure seeds are available to farmers and adequate fodder is supplied for livestock, as well as prioritising drinking water from low-level reservoirs.

Bahuguna said next week's meeting could consider offering farmers more money for subsidised diesel, which is used to run pumps for irrigation. (Reporting by Mayank Bhardwaj; Editing by Jo Winterbottom and Anthony Barker)