(Adds Shafik comments)
CAIRO, Jan 9 (Reuters) - Ousted Egyptian leader Hosni Mubarak's last prime minister, Ahmed Shafik, said in a television interview broadcast on Thursday that he would run for president if the army chief does not contest elections.
"I believe now I will run for the presidency," Shafik told Al Qahira Wil Nas television, adding that he would compete if army chief General Abdel Fattah al-Sisi stayed out of the race that is expected later this year.
Shafik left Egypt last year after being defeated in the presidential election by Mohamed Mursi, the Muslim Brotherhood politician since overthrown by the army and now on trial for conspiracy and inciting violence while in office.
Last month, Egyptian courts acquitted him in one corruption case and shelved another.
Shafik's return would reflect a shift in the balance of power in Egypt since the army removed Mursi and set the Arab world's largest nation on a new course designed to lead to presidential and parliamentary elections.
The next milestone is a Jan. 14-15 referendum on a new constitution.
Shafik, a former air force commander who cited Mubarak as a role model during his election campaign, lost narrowly to Mursi in the run-off.
Speaking from the United Arab Emirates, Shafik said it was possible he would return to Cairo to vote in the referendum.
In an interview in September, he said he would not run for the presidency if Sisi did and added that Sisi had his full support.
Sisi has yet to say if he will run. He enjoys wide support among those Egyptians who rejoiced at Mursi's overthrow, but he is reviled by the ousted president's supporters. Dates for presidential and parliamentary elections have yet to be set.
Egyptian security forces have mounted one of the toughest crackdowns on the Brotherhood in its history, killing hundreds of its members and arresting top leaders.
In an apparent attempt to capitalise on widespread anti-Brotherhood sentiment, Shafik called for maximum force to be used against the group.
Islamist militant groups have stepped up bombing and shooting attacks on Egyptian security forces since Mursi's overthrow, raising fears of prolonged instability in the biggest Arab state. (Reporting by Michael Georgy; Editing by Ken Wills)