I read about this , and men are forbidden from doing so, it is a big sin . If he gave talaaq and denied, then fuqaha went ٢ ways:
1) A woman should seek khula , coz she has no other witness.
2) A man has to take an oath , then a woman has to stay with her husband and he bears the sin.
But in actual talaaq tu hogai na ab husband maney yan na maney par dono ab na mehram howy ek dusrey k liye.