Mike Ashley's Sports Direct is set to acquire House of Fraser's Dublin store but must deal with regulatory issues before a takeover can be complete, according to administrators EY.

It comes after Sports Direct struck a deal to rescue House of Fraser's UK operations out of administration for £90m.

In a stock market announcement, Sports Direct said it has acquired all of the UK stores of House of Fraser, the brand and all of the stock in the business.

Some 17,000 staff are being informed that they will be transferred over from House of Fraser to Sports Direct.

House of Fraser's outlet in Dundrum, Dublin - its only outlet in the Republic of Ireland - employs more than 200 people as well as concession staff.

In a statement EY, which was appointed joint administrators of the retailer, said certain regulatory matters "need to be considered before the Sports Direct Group can complete their proposed acquisition of the Dundrum store."

It said that the store did close earlier to allow staff to be briefed on the matter, however it has since reopened and will "continue to trade as normal during the administration process."

Earlier trade union Mandate expressed serious concern on behalf of staff and has sought further information from the retailer.

A spokesperson for the union said it had put questions to House of Fraser earlier this week in relation to the future of the Irish store but has not received a response.

Mr Ashley's deal was struck through a pre-pack administration process, where a company is put into administration before a new buyer cherry picks the best assets.

It is believed that Sports Direct will attempt to keep as many House of Fraser stores open as possible following the takeover.

However, doubt remains over the long-term future of jobs and whether Mr Ashley will shut underperforming stores as part of a restructuring programme.

The billionaire, who also owns Newcastle United, said that Sports Direct will "do our best to keep as many stores open as possible".

In the same breath, he said: "My ambition is to transform House of Fraser into the Harrods of the high street."

The Sports Direct chief added: "This is a massive step forward and further enhances our strategy of elevation across the group.

"This will benefit both House of Fraser and Flannels in the luxury sector.

"It is vital that we restore the right level of ongoing relationships with the luxury brands. Our deal was conservative, consistent and simple."

Sources said that Mr Ashley will now begin the process of turning some House of Fraser stores into Sports Direct outlets and rebrand others under the Flannels fascia.

The House of Fraser deal will see the Newcastle United owner tighten his grip over the British high street, adding to his sports retailing and "premium fashion" empire.

The billionaire has also built up stakes in rivals such as Debenhams, Goals Soccer Centres and French Connection.

He also owns the Heatons chain in Ireland.

House of Fraser was plunged into crisis last week after C.banner, the Chinese owner of Hamleys, pulled its investment in the troubled retail chain.

C.banner was planning to buy a 51% stake in House of Fraser and plough £70 million into the ailing retailer, but then scrapped the move.

Prior to the latest crisis, House of Fraser had recently agreed a so-called Company Voluntary Arrangement with landlords to close half of stores, with 6,000 jobs in the firing line.

It is unclear what the status of the CVA is following the takeover.

Like other retailers, House of Fraser has been stung by soaring costs and falling consumer spending power.

The company saw its business rates bills rise £3.99 million to £30.24 million this year following a government revaluation, according to research group Altus.

Richard Lim, of Retail Economics, said: "This is a hugely ambitious move for Sports Direct. The combination of both businesses will yield some vital cost-saving synergies while it's likely that some of the struggling House of Fraser sites will be rebranded to Sports Direct.

"Nevertheless, this is a part of the industry that is under a huge amount of pressure. Turning around the business will not come easy. The stores are failing to attract sustainable levels of footfall while battling against rising operating costs and shifts in shopper behaviour."