Rangers chairman Dave King will be taken to court over his failure to make a mandatory offer for shares in the club's holding company.

The Takeover Panel has opened proceedings at the Court of Session after the South African-based businessman refused to comply with their order to bid for 66% of Rangers International Football Club plc.

King was ruled by the Takeover Appeal Board in March to have acted "in concert" with other shareholders to seize control of Rangers in 2015.

He was ordered, in line with the Takeover Code, to offer 20p for every share not owned by himself or the other members of his concert party.

A statement from the Takeover Panel read: "On March 13, 2017, the Takeover Appeal Board published its decision upholding rulings of the Takeover Panel Executive and of the Hearings Committee of the Takeover Panel that Mr David Cunningham King acted in concert with Messrs George Letham, George Taylor and Douglas Park to acquire more than 30% of the voting rights in Rangers and in consequence had incurred an obligation under the Takeover Code to make a mandatory offer at a price of 20 pence per Rangers share for all of the Rangers shares not already held by Mr King and members of his concert party.

"The Takeover Appeal Board directed that Mr King should announce an offer pursuant to Rule 9 of the Takeover Code by April 12, 2017.

"No such offer having been announced, the Takeover Panel has today initiated proceedings in the Court of Session, Edinburgh under section 955 of the Companies Act 2006 seeking an order requiring Mr King to comply with these rulings."

Mr King had appealed against the initial findings of the takeover panel last year, arguing he was separate from New Oasis Asset Limited, a British Virgin Islands company which acquired his 14.5% shareholding in Rangers from institutional investors in 2015.

The appeal board found New Oasis was ultimately owned by Mr King for "the benefit of himself and members of his family" through a Guernsey-based trust.

The appeal board noted: "We have reached the conclusion, having regard to the grounds and basis of the appeal and taking account of all the evidential materials placed before the board, that Mr King was acting in concert with Messrs Letham, Taylor and Park in the acquisition of the shares in Rangers on December 31, 2014, and January, 2, 2015. On the 'acting in concert' point we uphold the findings and ruling of the committee."

The takeover appeal board also criticised the businessman for a "lack of cooperation" in its investigation.