Yemen's outgoing president Ali Abdullah Saleh said on Tuesday he would return home from the United States before an election later this month designed to choose his successor.
Saleh has repeatedly voiced plans to return to Yemen, but his intention to do so before the vote will raise doubts about his commitment to leave office in line with a Gulf-brokered deal to end a year of political upheaval in the impoverished state.
Saleh, who formally transferred power to his deputy Abd-Rabbu Mansour Hadi in November, flew to the United States last month to undergo medical treatment for wounds inflicted during an assassination attempt last year.
"I will return to the land of the nation after the end of my treatment to be present during the election," Saleh said in a statement posted on the defence ministry's website.
The election, scheduled for Feb 21, has already run into problems. Both southern separatists and rebels in the north have said they will boycott it.
Hadi, the only candidate for the position of president, said on Tuesday he would open dialogue with both groups.
"We are determined to overcome our crisis through dialogue and logic, not weapons," he said in a speech to mark the launch of his election campaign. "This is for the sake of rebuilding a Yemen free of terrorism and corruption."
Four southern separatists were injured late on Monday when security forces shot them as they tried to burn down a local office of Saleh's People's Congress Party and election committee offices in Hadramout, residents said.
They said the separatists, part of a movement demanding a revival of the southern Yemeni state that Saleh united with the north in 1990, were taking part in a demonstration and a general strike against elections in Hadramout province.
Washington fears that a low voter turnout could dent the legitimacy of Hadi, the man it is counting on to steer Yemen away from civil war during a critical two-year interim period.
Even if the election goes smoothly, Yemen faces a daunting list of security challenges, not least a regional wing of al Qaeda, which has exploited weak central government control to seize territory in the country's south.
One Yemeni soldier was killed and two were injured on Tuesday when unidentified militants attacked an army convoy in the southern province of Lahej before fleeing the scene on motorcycles, a security source said.
Separately, an al Qaeda militant identified as Zain al Jundi was injured by security forces while trying to escape from a prison in the southern province of Abyan, the defence ministry said on its website. He was recaptured but two of his comrades escaped, it said.
The United States and oil giant Saudi Arabia fear unrest in the impoverished Arab country is giving al Qaeda's Yemen wing a chance to expand its control along key oil shipping lanes.