Newcastle United have agreed a £19.6million deal with Ajax for Sean Steur.The fee will rise to £22.6m with add-ons for the 18-year-old midfielder who is set to join on a five-year deal.The Netherlands Under-19 international has made 25 appearances for Ajax and is regarded as a top talent.However, Ajax need funds to strengthen their squad and also have young Belgian midfielder Jorthy Mokio who can play in the same role.They have also asked for a 12.5 per cent sell-on clause. 18-year-old Ajax midfielder Sean Steur looks set to join NewcastleAs Daily Mail Sport revealed last week, Newcastle are continuing to work on a move for Freiburg’s £40m-rated Johan Manzambi, and are considered frontrunners for the Switzerland international midfielder despite interest building from other clubs.Newcastle have already seen Sandro Tonali depart for Tottenham in a deal that could be worth up to £100million while Arsenal maintain interest in Bruno Guimaraes.