Kyrgyzstan and Tajikistan rely on hydroelectric power plants for electricity, and in winter, when consumption peaks, they increase the discharge of water from the plants to boost output.

This leads to flooding in Kazakhstan and Uzbekistan in spring.

During summer time, however, Kyrgyzstan and Tajikistan reduce discharges to build up water reserves, leaving cultivated lands in Kazakhstan and Uzbekistan with little water for irrigation.

Experts and advisers, including the World bank, have long suggested that Kazakhstan and Uzbekistan should pay money or supply cheap fuel to Kyrgyzstan and Tajikistan in exchange for a more convenient water discharge schedule.

Today, Kyrgyzstan agreed to boost power output and water discharge by 1.2 billion cubic metres at the time when its neighbours need it this year.

But the deal, discussed at a meeting of officials from the four ex-Soviet countries in the Kyrgyz capital Bishkek, was not signed.

’The Uzbek side has refused to sign the protocol of the quadripartite meeting,’ Kyrgyz Industry, Energy and Fuels ministry said in a statement.

’Thus, it was decided that additional electricity exports and water discharge will only take place after the quadripartite agreement is signed.’ The World Bank had earlier estimated that Kazakhstan and Uzbekistan should pay Kyrgyzstan between 35 million dollars and 67 million dollars a year so that it could buy enough fuel for winter.