United confirmed on Thursday they had completed the signing on French defender John Licina.
The former Sochaux man, who is 24, impressed against St Mirren when he came on as sub on Saturday and earned a starting place in Wednesday's derby at Dens Park. He has signed a two-year contract with the Club and Manager Alex Smith is looking forward to working with him.
"John has worked hard and shown a great attitude. He deserves this deal and I am sure he will be a valuable member of the squad."