Donald Trump is under pressure from Hillary Clinton to disclose all pro-Russia ties after the The New York Times reported a Ukrainian ledger showed millions of dollars earmarked for his campaign chairman.

The so-called “black ledger” apparently showed that the political party of former Ukraine president Viktor Yanukovych designated $12.7m (£9.9m) in cash payments to Paul Manafort between 2007 and 2012. Investigators for Ukraine’s National Anti-Corruption Bureau said the money was part of an illegal “off-the-books” system of payment.

Mr Manafort vehemently denied the allegations from the New York newspaper, saying that there is no evidence to suggest he accepted such payments.

Additionally, investigators found that Mr Manafort was a part of an $18m deal to sell Ukrainian cable television assets, which prosecutors linked to offshore shell companies. Prosecutors are not focusing on Mr Manafort in this aspect of the investigation, but feel that he must have known the nature of the business.

“He understood what was happening in Ukraine,” Vitaliy Kasko, a former official at the general prosecutor’s office in Kiev, told The New York Times. “It would have to be clear to any reasonable person that the Yanukovych clan, when it came to power, was engaged in corruption.”

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Mr Kasko added that it was “impossible to imagine” somebody like Mr Manafort would think the financial dealings were legitimate.

“Once again, The New York Times has chosen to purposefully ignore facts and professional journalism to fit their political agenda, choosing to attack my character and reputation rather than present an honest report,” said Mr Manafort. “I have never received a single ‘off-the-books cash payment’ as falsely reported by The New York Times, nor have I ever done work for the governments of Ukraine or Russia.”

“The suggestion that I accepted cash payments is unfounded, silly, and nonsensical.”

Indyplus gallery: Inside the lavish residency of fugitive president Victor Yanukovych Show all 21 1 /21 Indyplus gallery: Inside the lavish residency of fugitive president Victor Yanukovych Indyplus gallery: Inside the lavish residency of fugitive president Victor Yanukovych Ukraine Mansion A staircase winds up in a view of a room inside President Viktor Yanukovych's Mezhyhirya estate, which he abandoned as further evidence of his corrupt behaviour continues to surface from the incriminating documents found at his mansion Indyplus gallery: Inside the lavish residency of fugitive president Victor Yanukovych Ukraine Mansion Books are left out on a desk inside President Viktor Yanukovych's Mezhyhirya estate. Former President is believed to have left his residence outside Kiev, where Ukrainians have discovered a private zoo, mock galleon and a number of vintage cars that their taxes and the corruption he presided over helped to fund Indyplus gallery: Inside the lavish residency of fugitive president Victor Yanukovych Ukraine Mansion Former Ukrainian president Viktor Yanukovych is wanted for ‘mass murder’ and is believed to have evaded security forces by fleeing the country in a helicopter during a three-day dash for freedom Indyplus gallery: Inside the lavish residency of fugitive president Victor Yanukovych Ukraine Mansion A white piano sits in one of the rooms inside President Viktor Yanukovych's Mezhyhirya estate Indyplus gallery: Inside the lavish residency of fugitive president Victor Yanukovych Ukraine Mansion A view of Viktor Yanukovych's Mezhyhirya bedroom Indyplus gallery: Inside the lavish residency of fugitive president Victor Yanukovych Ukraine Mansion Balls are left on a billiards table in a room inside President Viktor Yanukovych's Mezhyhirya estate Indyplus gallery: Inside the lavish residency of fugitive president Victor Yanukovych Ukraine Mansion A collection of ammunition is displayed in cases inside President Viktor Yanukovych's Mezhyhirya estate Indyplus gallery: Inside the lavish residency of fugitive president Victor Yanukovych Ukraine Mansion After Viktor Yanukovych's leaving the capital Kiev, the campus containing Yanukovych's residence put under protection by anti government protestors, charms the visitors in Kiev. Houses of Yanukovych, a heliport, boxing ring, places for animals, gas station, a garage for more than 50 cars, a golf range, an artificial lake and waterfalls, many food courts, ships and the scenery of Dnieper River from Yanukovych's residence adorn the campus. People raiding to the campus, look at the former president's golden toilet and taps, valuables in luxurious yacht Indyplus gallery: Inside the lavish residency of fugitive president Victor Yanukovych Ukraine Mansion A group of opposition activists take over a mansion allegedly connected to former Ukrainian president Yanukovich's family and close circle in Koncha Zaspa area near Kiev Indyplus gallery: Inside the lavish residency of fugitive president Victor Yanukovych Ukraine Mansion An exterior view of the main building in the residence of Ukrainian President Viktor Yanukovych EPA Indyplus gallery: Inside the lavish residency of fugitive president Victor Yanukovych Ukraine Mansion People wander and take photos around President Viktor Yanukovych's Mezhyhirya estate, which was abandoned by security in Kiev Indyplus gallery: Inside the lavish residency of fugitive president Victor Yanukovych Ukraine Mansion People take a photo in front of the Viktor Yanukovych's Mezhyhirya estate Indyplus gallery: Inside the lavish residency of fugitive president Victor Yanukovych Ukraine Mansion A man sings karaoke in the empty mansion Indyplus gallery: Inside the lavish residency of fugitive president Victor Yanukovych Ukraine Mansion People look through windows of the Mezhyhirya residence of Ukraine's President Viktor Yanukovich Reuters Indyplus gallery: Inside the lavish residency of fugitive president Victor Yanukovych Ukraine Mansion Viktor Yanukovych's personalised bottles with alcohol Indyplus gallery: Inside the lavish residency of fugitive president Victor Yanukovych Ukraine Mansion A luxurious bar is found on Victor Yanukovych’s presidential lodgings Reuters Indyplus gallery: Inside the lavish residency of fugitive president Victor Yanukovych Ukraine Mansion A protester poses in a bathtub at the residence of Ukrainian President Viktor Yanukovych EPA Indyplus gallery: Inside the lavish residency of fugitive president Victor Yanukovych Ukraine Mansion Other protesters took the opportunity to use the facilities on the abandoned estate Indyplus gallery: Inside the lavish residency of fugitive president Victor Yanukovych Ukraine Mansion Protesters sort captured documents at the residence of Ukrainian President Viktor Yanukovych EPA Indyplus gallery: Inside the lavish residency of fugitive president Victor Yanukovych Ukraine Mansion This collection of cars was left behind in pristine condition Indyplus gallery: Inside the lavish residency of fugitive president Victor Yanukovych Ukraine Mansion A man holds a golf club with the name of Ukrainian President Viktor Yanukovich on a golf course at the Ukrainian President Yanukovych's countryside residence AP

Mr Manafort’s comments echo an earlier defence made by Mr Trump, when the newspaper published a report detailing troubles within the campaign, the property tycoon accused The New York Times of fabricating stories to promote a pro-Clinton bias.

But the latest report inflamed concerns from the Clinton campaign, especially given Mr Trump’s recent off-hand remarks suggesting Russian intelligence should hack his Democratic opponent.

“Donald Trump has a responsibility to disclose campaign chair Paul Manafort’s and all other campaign employees’ and advisers’ ties to Russian or pro-Kremlin entities,” said Clinton campaign chairman Robby Mook.

However, Mr Manafort maintains that he simply did work as a “campaign professional” for an international campaign when he worked with Mr Yanukovych.

Mr Manafort began his work as a consultant for the Party of Regions and Mr Yanukovych, first unofficially in 2004, then officially in 2006.

“My work in Ukraine ceased following the country’s parliamentary elections in October 2014,” Mr Manafort said.