New Delhi, Sep 10 - Veteran actress Sharmila Tagore loves watching her son's films as any mother does and feels his acting has improved phenomenally over the years. At the same time she says Saif Ali Khan is not the easiest of actors to work with.

'As an actor, Saif has grown by leaps and bounds. I think in 'Love Aaj Kal', his monologues are really good. And over time, he has become a very sensitive actor. I am really proud of him,' Sharmila told IANS in an interview.

Talking about some of her favourite Saif-starrers, the 62-year-old actress named films like 'Love Aaj Kal', 'Omkara', 'Parineeta', 'Ek Hasina Thi', 'Hum Tum', 'Being Cyrus', 'Kal Ho Na Ho' and 'Dil Chahta Hai'.

'They are all such different roles that he has played and in such a variety of films. I feel he has an energy in him that makes me want to see him on screen,' she said.

If Sharmila is to be believed, Saif is not an easy actor to work with and says she is confident that he would have been a menace for most of his directors.

'I really don't know how the directors work with him. He is a difficult actor to work with. The directors probably pull their hair out. How it happens I don't know, but I like what I see of him on screen,' she said.

The mother and son have featured together in 'Aashik Aawara' (1993) and 'Eklavya - The Royal Guard' (2007).

'He has been very lucky to work with people like Vishal Bharadwaj, Imtiaz Ali, Pradeep Sarkar and Farhan Akhtar, who have given him meaningful and meaty roles,' she added.

According to the doting mother of three - Saif, Soha and Saba, her son's most forgettable role has been in 'Tashan', where he was cast with Kareena Kapoor.