Dundee United close to capturing ex-Hearts, Leicester defender Neilson
The 31-year old former Heart of Midlothian and Leicester City defender is set to sign with the Arabs until the end of the season as a free agent and Houston is happy he chose Tannadice over some clubs in England.
"We've agreed terms and Robbie will sign until the end of the season," said Houston.
"If he does well, I'd be looking to keep him on for next season.
"He brings great experience and will be in the squad for Saturday's game against Hearts, a club he played with for a good number of years.
"The thing about Robbie is he can cover a number of positions so he can fill in anywhere in the back four.
"Robbie is at the stage where he just wants to get back playing. He's had offers from English clubs, but wants to come back to Scotland and sign for us."