Mackay had claimed at the weekend he hoped to bring in three new players to improve his squad for the second half of the Premier League season.

But Cardiff's chief executive Simon Lim released a statement on Monday outlining the club's stance on spending in which he claimed Tan was jolted by Mackay's announcement that he would seek backing from the board for squad strengthening.

Lim said it was Tan's view that the club overspent in the transfer market by �15 million ahead of the season.

"Tan Sri Vincent Tan was extremely upset to read quotes from the manager concerning the possibility of new recruits, before he had been informed whether funds would be made available," Lim said.

"He believes that doing so unfairly raises supporter expectations, placing unnecessary pressure on the club.

"His view is that due to the funds already committed, including the originally authorised summer transfer budget of �35m that rose to �50m in total, including add-ons, the manager has been fully supported.

"The overspending of �15m has upset Tan Sri greatly, resulting in the removal on Iain Moody as head of recruitment. As such, he has stated that not a single penny will be made available in January.

"Having been the highest-spending promoted club and the seventh-highest spender in the Premier League last summer, the owner believes that the manager has been given the best possible chance of retaining our Premier League status."

Mackay was allowed to spend big money on the likes of Steven Caulker, Gary Medel, Kevin Theophile-Catherine and Andreas Cornelius following last season's promotion from the Championship.

But Cardiff stand just four points outside the relegation zone despite that significant outlay and the Bluebirds boss was hoping he would receive the board's cheque-book backing in January to bolster their survival bid.

The fact Tan has indicated that will not be happening may be of some concern to the Scot, who is in his third season at the club.

Mackay has already had to survive one round of speculation about his position after Moody was replaced by Kazakh 23-year-old Alisher Apsalyamov in October.