Describing his father's deportation to Saudi Arabia as "a bad day in the history of Pakistan," Nawaz Sharif's son on Monday warned the Pervez Musharraf [Images] regime that the former premier would return to the country "as soon as he can."

"It is a very bad day in the history of Pakistan," Hasan Sharif said.

"The events we have witnessed... will never be a happy ending for the people of Pakistan," he told Sky News.

Hasan said his father was "disappointed" to have been deported from Pakistan, but would make his "plans" available to the entire world "very soon."

"He is very disappointed, but equally he has very high spirits. He is a very courageous man. Everybody witnessed what he did today," he said.

"Please let me say Mr Musharraf, make no mistake about it, he will be back," Hasan said.

"Forcing him to go back to Saudi Arabia... against my father's will will never be a happy ending for the people of Pakistan," Hasan said.

Asked about his father's plans, he said for the moment he is "very very tired" after the trip to Pakistan and then back to Saudi Arabia.

"But of course that will not stop him thinking about the Pakistani people... about restoring democracy in Pakistan and I'm sure in the not too distant future he will come out with a very solid plan."

"He has the right to go back to Pakistan. He will go back to Pakistan as soon as he can," he said.

Hasan said his father "will make his plans available to the entire world very, very soon."