New Delhi: The Congress has alleged that two different kinds of Rs 500 and Rs 2,000 notes were printed post demonetisation, "jeopardising the credibility" of Indian currency, and demanded that Prime Minister Narendra Modi clear the air on the issue. The opposition party, which disrupted proceedings in the Rajya Sabha over the issue forcing its adjournment for the day, said the "discrepancies" in the printing of the new high denomination notes were in terms of their size, design and other features. It asked Modi and Finance Minister Arun Jaitley to explain as the issue "raises questions over the country's financial structure". The party, however, said that the different notes "are not counterfeit" currencies since they are all printed under the aegis of the RBI and the Ministry of Finance and incorporated most of the security features published in the official website of the bank. Senior Congress leader Kapil Sibal, who flagged the issue in the Rajya Sabha earlier in the day calling it the "biggest scam of the century", said the opposition party would keep raising it in Parliament until the government explains its stand on the issue. The former Union minister also alleged that the demonetisation move "failed" to achieve its stated objectives of combating black money, corruption, counterfeit currency and terrorism. In this context, he demanded that the government explain the motive behind invalidating the old Rs 500 and Rs 1,000 currency notes. "First they should explain which dye was used (for printing the notes), what types of notes were printed, at which printing press the notes of different sizes were printed." The difference in the currency notes, "jeopardises credibility of the currency. The prime minister, finance minister, RBI governor should come to the fore and explain," Sibal told reporters here. He said that when demonetisation was announced, there were messages on social media alleging that leaders of the BJP had new Rs 2000 notes with them even as people queued up outside banks and ATMs. He also accused the ruling BJP of spending huge amount of money during Uttar Pradesh assembly polls held earlier this year. "How was that possible? The government should tell where the notes were printed," he said. Sibal said, according to the RBI's official website, the standard size of the Rs 500 note is 66 mm X 150 mm, whereas that of the Rs 2000 note is 66 mm X 166 mm. However. He claimed some Rs 500 notes were longer, allegedly ranging between 151 mm and 153 mm. The "discrepancy" with regard to length was found in case of Rs 2,000 notes too, he said and claimed some notes were 167 mm long. The sizes of the right, left, top and bottom borders of some notes too allegedly differed from the RBI standards and so did the designs on their corners, Sibal added. "Where were the notes of significantly different sizes printed? Nowhere in the world are currency notes of whatever denomination of different sizes. "Different size of currency notes has huge global ramifications. Indian citizens will be confused about the authenticity of the currency," he alleged. The shade mark on the left of Rs 500 currency "was darker on some notes" vis- -vis other notes. The placing of Ashoka pillar emblem on the notes too was allegedly not similar. The bleed lines, on the left and right side borders of the notes, also differed from each other in length, he claimed. The words 'Mahatma Gandhi' on some Rs 2000 notes were printed above the shaded portion at the bottom. On standard size Rs 2000 notes, the text touched the shaded portion of the bottom, he claimed. "The prime minister, hence, should tell the people, why the difference in designs, sizes and features of the notes? Why there are differences in consecutive notes of the same series as well?" he asked. The leader also sought to know whether the "different" notes were printed without the RBI's permission. "If they were printed with the top bank's nod, why were people allegedly not informed about it," he questioned. "Whether these notes were printed inside India? If yes, where and how many? If these were printed outside India, why were they printed abroad?" he demanded to know. When asked by a reporter about Union Minister Mukhtar Abbas Naqvi's allegation that the Congress was "misleading" the people, Sibal retorted "only time will tell who is doing so".