1MDB and the Minister of Finance (Incorporated) Malaysia (MOF Inc) have paid up all that is due to Abu Dhabi's International Petroleum Investment Company (IPIC) for this year.

This was announced by IPIC in a filing to the London Stock Exchange and a press release by 1MDB today.

"All funds were paid from proceeds of the on-going rationalisation programme," read the brief statement from 1MDB. 

1MDB and its owner, MOF Inc, had reached a settlement with IPIC in April, in which US$1.2 billion was to be paid to the latter in two equal tranches on July 31 and Dec 31.

Filings by IPIC earlier this year indicated that it was attempting to recover US$6.5 billion and interest charges from 1MDB. 

[For details, read our KiniGuide: 1MDB's debt payment plan and how it doesn't add]

The July 31 deadline was not met and an extension was granted. When the sum was finally paid up, it appeared to have incurred late payment charges, which neither party explicitly confirmed.

In 2012, IPIC became entangled in 1MDB's complicated web of global transactions by guaranteeing a US$1.75 billion bond issued by the Malaysian company.

By 2015, 1MDB was facing severe cashflow problems, prompting a deal in which IPIC would pay off creditors who were seeking US$1 billion.

1MDB is a sovereign wealth fund established by Finance Ministry in 2009 following Najib Abdul Razak's ascension to the premiership.

The company even appointed him as its advisor and gave him some executive powers.