The Clarets were closing in on a double deal for Muleka and Standard and DR Congo teammate Samuel Bastien.
Muleka – who scored 12 goals in 14 appearances last season on loan from Liege at Turkish Superlig side Kasımpaşa – is also a target for Besiktas, with Kasımpaşa also keen to be reunited with the 22-year-old.
The two clubs are believed to have reached an agreement around €4m plus add ons for Muleka, with the Belgian club getting a sell on clause of 25%, with them having to pay 50% of this sale to his former club TP Mazembe.
Muleka was expected to sign a four-year contract, having had the first part of his medical in Belgium on Thursday, with the second to follow in England.
He also had to wait for approval for a visa, which, it was suggested, could be issued early this week.
However, sources in Belgium understand the transfer is of at this moment, with “several reasons for the possible cancellation”.
Muleka will now link up with Standard on their training camp in the Netherlands.
However, the Bastien deal is still likely to go through, with an €800,000 fee agreed for a player in the final year of his contract.
Bastien came through Anderlecht's youth system, making his first team debut in December 2014 in the Belgian Cup against Mechelen, replacing Youri Tielemans.
He spent time in Italy on loan with Avellino before joining Serie A side Chievo Verona for €2.5m, joining Standard in June 2018.
In Belgium, Burnley have again been linked with a €2m move for Anderlecht’s Republic of Ireland midfielder Josh Cullen, while 19-year-old Dutch goalkeeper BartVerbruggen.