Rúben Amorim is set to be confirmed as Manchester United’s manager after Sporting said the Premier League club were ready to pay his release clause of €10m (£8.3m).

Sporting issued a statement to Portugal’s financial regulator, the securities market commission, saying United “had expressed interest” in hiring the 39-year-old and paying the termination fee.

United entered talks with Amorim’s representatives after sacking Erik ten Hag on Monday, offering a three-year deal worth about £6.5m a season. Amorim will take charge of Sporting’s cup game at home to Nacional on Tuesday night and United are working to announce his appointment as quickly as possible. They have Ruud van Nistelrooy in temporary charge for Wednesday’s Carabao Cup tie at home to Leicester and face Chelsea in the league at Old Trafford on Sunday.

United will have a limited budget for their manager to strengthen the squad in January. After Ten Hag was backed in the summer with a £200m spend on five players – Joshua Zirkzee, Leny Yoro, Matthijs de Ligt, Noussair Mazraoui and Manuel Ugarte – there is only modest finance to try to turn around the side’s fortunes in the winter window.

Although the manager will not have to sell to buy, profitability and sustainability rules mean the books will need to be balanced via sales if he wants to spend more lavishly. About £600m has been invested in building a squad for Ten Hag over the five windows of his two-plus seasons in charge.

Beyond Alejandro Garnacho, Rasmus Højlund and Kobbie Mainoo, who are ringfenced as not for sale, United have a paucity of high-end assets, with Marcus Rashford, who could draw about £60m, perhaps of the highest value.

Sporting prepared on Tuesday for Amorim’s departure by agreeing a deal for João Pereira, the coach of their reserves, to succeed him. They have won two league titles and two League Cups in Amorim’s four full seasons and are top with a 100% record after nine matches of this campaign.

United are 14th in the Premier League after nine games, with 11 points, eight goals and a goal difference of -3. In the Europa League they are 21st of 36 teams after drawing their opening three matches.

Arne Slot believes Ten Hag, who he has faced in the Premier League and Eredivisie, will soon get another job with a leading club. “[I know] how well he did at Ajax and that he won two trophies over here so we will see him I think in the near future at a big club again,” Liverpool’s head coach said.