A sub-committee of the Public Accounts Committee has recommended to the government a CBI inquiry into the 'intriguing chronology' of decisions taken by former finance minister P Chidambaram on banning gold import and subsequently approving the 20:80 scheme for importing the metal 18 days later in mid-2013, sources privy to the development told ET.The sub-committee also wants CBI to look into an RBI circular issued during the tenure of Raghuram Rajan on May 21, 2014 - five days after UPA regime was voted out - notifying the finance ministry's decision taken a day before the Lok Sabha results, to amend the 20:80 scheme for allowing gold import by Star Trading House (STH) and Premier Trading House (PTH). Gitanjali Gems that figures in the PNB scam, is, incidentally, a STH.Being a quasi-judicial body, recommendations of PAC's sub-committee is as good as a directive. The CBI had approached the Supreme Court seeking re-opening of the Bofors case after a similar directive by a PAC sub-committee.Sources said the PAC sub-committee headed BJP Lok Sabha member Nishikant Dubey decided to pitch for a CBI probe into the 20:80 scheme after it scrutinised a 'chronology of decisions' taken by the then FM. The sub-committee had sought the chronology from a concerned government department and had it received on Monday.Sources said the sub-committee found two aspects of the 'chronology of decisions' intriguing: Chidambaram on June 3, 2013, directed "Foreign Trade Policy should be amended to prohibit many organisations from importing gold except for very narrow/limited purposes". The high current account deficit was the official reason given. However, 18 days later the then FM "approved the 20:80 scheme". The sub-committee, sources said, wants to probe what all happened in the 18 days between the decisions of prohibiting gold import to its partial lifting and what all prompted the decisions.According to sources, on June 4, 2013, RBI issued guidelines whereby gold import on consignment basis were permitted by nominated agencies and banks only to meneeds of exports of gold jewellery. On June 13, 2013, "a meeting of various stakeholders was called and it was decided that all nominated agencies/designated banks importing gold shall have to meet, lot wise a ratio of 20:80 between exporters and the domestic manufacturers".Sources said the second pattern of decision that 'alerted' the PAC sub-committee was that of May 13, 2014, three days before the 2014 Lok Sabha results, when the then FM gave "his approval for inclusion of STH/PTH for import of gold under 20:80 scheme. And on May 15, 2014, officially the last day of UPA-2, the Department of Economic Affairs wrote to RBI to amend the 20:80 scheme to allow gold import by STH/PTHs." Five days after UPA was voted out, "RBI issued AP Dir Circular to amend 20:80 scheme to allow gold import by STH/PTHs".Sources said that prior to the May 13 decision, at "a meeting in January 2014, attended by representatives from RBI, DGPT, DGEP, CBEC, it was decided that the request of STH/PTHs for their inclusion in 20:80 scheme may be considered after assessing the amount of gold likely to be imported by them," sources added citing the chronology.Subsequently, the finance minister of the NDA government approved withdrawal of 20:80 scheme on November 27, 2014, and the very next day the RBI issued AP Dir to withdraw 20:80 scheme with immediate effect.