Presidential spokesman Farhatullah Babar said Zardari returned on January 13 from a trip to Dubai that had raised concerns that he was being pushed out of office.
Babar said Zardari, who is under pressure from the military, went to Dubai on January 12 to attend a wedding.
The one-day trip came amid a spat between Pakistan's civilian leaders and the military over a probe into the government's role in a scandal centered on a mysterious memo that purportedly sought U.S. help in curbing the army's power.
The president traveled last month to Dubai for medical reasons, triggering widely reported rumors he was on the verge of resigning.
Babar, however, said Zardari was "absolutely not" concerned about his political future.
Meanwhile, lawmakers on January 13 introduced a resolution in parliament to express support for the government.
The resolution, which would give a symbolic boost to Zardari, faces a vote on January 16.
Prime Minister Yousuf Raza Gilani, a Zardari ally, said the measure pledges "full confidence and trust" in the political leadership.
On January 11, the military warned of "serious ramifications with potentially grievous consequences" after Gilani criticized military leaders in an interview.
Meanwhile, Gilani sacked his defense secretary, retired Lieutenant General Naeem Khalid Lodhi, an army appointee in the government, for "gross misconduct."
compiled from agency reports