This never-ending saga – one that has infuriated the POTUS, Donald Trump, who had received assurances this investigation would conclude before thanksgiving last year – rumbles on.

According to the New York Daily News, Special Counsel Robert Mueller has turned his attention to a number of suspicious financial transactions that took place at key moments before and after the US election of 2016.

The recent book, Fire and Fury, written by journalist Michael Wolff, reveals that even erstwhile close Trump aide Steve Bannon, who has now been summoned to testify in the Russia probe, suggested that “this is all about money laundering”, and that the German bank Deutsche Bank, was at the heart of some questionable dealings.

Deutsche have been subpoenaed as part of Mueller’s investigation; the bank is also embroiled in a money laundering investigation being carried out by British and New York regulators, related to a $10 billion scheme originating from Russia.

Donald Trump is also said to have a close relationship to Deutsche, disclosing in June that he is in debt to the bank to the tune of $130 million – the real figure, according to the Financial Times is closer to $300 million.

It is one thing suspecting money laundering, however, but quite another proving it. Last week, an investigation by BuzzFeed revealed that banks, including Citi, have been flagging payments made by the Russian Embassy in the US, since long before the 2016 election.

Buzzfeed say that officials in the Russia probe are now focusing on payments made by the Embassy to, amongst others, Sergey Kisylak, the former Russian Ambassador to the US.

Kisylak is alleged to have received $120,000 ten days after Donald Trump triumphed in the election. Kisylak is said to have split the payment in two, and transferred each separately to a different account in Russia. The transaction was marked as payroll, but was flagged by Citi, which handles all the Russian Embassy’s banking requirements, as being suspicious since it did not tally with prior payment patterns.

Citi also blocked an attempted withdrawal of $150,00 from the embassy’s account 5 days after the presidents’ inauguration, again flagging it as abnormal activity.

And there is more. The Russian Embassy sent $2.4 millions of payments to a home-improvement company, run by a Russian immigrant, in a series of more than 60 payments, that were labelled as payments for improvement work to the embassy.

The transactions were flagged by the bank again, who felt that the business was too small to have carried out such work, but there was no further investigation. Once the payments were received, it is said that the money was quickly transferred to other accounts, and soon became untraceable.

In two other incidents highlighted by BuzzFeed, $370,000 was apparently sent to employees at the embassy, in the form of cheques which were quickly cashed, again making tracing impossible, and a business known as the Russian Cultural Centre sent $325,000 in cheques that were again flagged as suspicious.

The Russian embassy has responded to the Buzzfeed article, issuing a statement declaring that “all the transactions which have been carried out through the American financial system fully comply with the legislation of the United States”, and adding that “we see such leaks by US authorities as another attempt to discredit Russian official missions.”

Citibank told Buzzfeed that “Citi is diligent in filing Suspicious Activity Reports with the Treasury Department when appropriate”, but declined to comment further.

Having already arrested Paul Manafort on alleged money laundering charges, and National Security Advisor Michael Flynn and campaign Advisor George Papadopoulos, for lying to investigators about meeting with Russian contacts during the election campaign, it seems that Robert Mueller is just getting started, and this inquiry is likely to run beyond even this year’s thanksgiving, after the government’s plea to have Manafort’s trial take place in May, was rejected.