Intelligence Bureau chief Ajit Kumar Doval has asked his officers in Punjab to explain why they failed to tip off the central government about the intentions of the Punjab government to scrap the 1981 river water agreement.

The agreement had Haryana, Himachal Pradesh and Rajasthan as parties, apart from Punjab.

The IB chief issued the directive on the orders of Prime Minister Dr Manmohan Singh.

"Our joint director in Chandigarh has been asked to probe the intelligence failure and report back to the IB chief," a senior official of the IB told rediff.com.

Sources confirmed that Punjab Chief Minister Captain Amarinder Singh had been toying with the idea of scrapping the agreement since the first week of June when the Supreme Court had directed the Centre to take over the construction of the Sutlej Yamuna Link canal and complete it within the stipulated timeperiod.

Even when the Punjab CM reconvened the state assembly on Monday to discuss the SYL issue the intelligence officers failed to smell a rat .

"It is a big slap on our intelligence set up. Most of the political leaders of the assembly knew what was coming but nothing was leaked out to either the media or any other official. Even the Congress top brass sitting in the capital did not have an inkling of what their own chief minister was up to," admitted a senior Indian Police Service official, who was once associated with the IB.