Former England Under-21 captain Reo-Coker is out of contract at the end of the season. But he has created a favourable impression with Houllier who restored him to the side after replacing Martin O'Neill as manager in September. He made him stand-in captain when skipper Stiliyan Petrov was sidelined through injury.
"I said to him and to his agent that we will have an assessment from the end of February to the beginning of March. But I know also there are clubs after him because he is a free agent," said Houllier.
"Nigel will play probably against Blackpool (on Sunday) and he is my player until the end of the season.
"Funnily enough, he is improving but there is not the situation where there is 11 players and the rest are not involved. To me when you have a big squad they should be united. You don't have sulkers and moaners. This is very important and Nigel plays a part, not only in the dressing room, but every time he steps on the field."
"I think Nigel's performances from the beginning of the season compared with now have been different. He is more calm and more composed and does things simple. He is a ball winner and gets forward when he can. I like his discipline, I like his commitment and his aggression."
Houllier has been pleased with the impact of Darren Bent since becoming Villa's ?£18 million record signing after his move from Sunderland last month.
Bent also impressed when scoring and playing the full 90 minutes for England against Denmark in Copenhagen on Wednesday.
Houllier said: "Goals have to come from everywhere. But Darren is a natural goal-scorer. You can see that in training. He is always at the end of the move to score. Since he has been here he has scored three goals - two for us and one for England. You could say he has been well trained!
"He scored immediately after coming here which is good for the confidence and for the player."
Source: PA
Source: PA