Pakistan's Army Chief Gen. Ashfaq Pervez Kayani, right, and Pakistan's Prime Minister Yousuf Raza Gilani, left, are seen in this April 10, 2010 photo. Pakistan’s prime minister fired his defense minister Wednesday, the latest salvo in an increasingly public civil-military feud. (Khalid Tanveer/AP)

An increasingly public battle between the military and the civilian government of this nuclear-armed nation escalated Wednesday, as the army warned that Prime Minister Yousuf Raza Gilani’s recent criticism of its chief could have “grievous consequences” and Gilani fired his defense secretary.

Adding intrigue to the drama, Pakistani President Asif Ali Zardari flew on Thursday to Dubai, United Arab Emirates, where he underwent medical treatment last month. An official in Zardari’s office said he was going to attend a medical checkup and a wedding and would return within two days. Meanwhile, the army chief held an emergency meeting with his top generals at army headquarters in Rawalpindi, fueling speculation about the military’s plans.

The developments sent Pakistan’s crisis-prone politics into a new tailspin, hardening a standoff that some analysts say could bring down the unpopular government. The turmoil appears likely to distract from efforts to repair frayed relations between the United States and Pakistan, complicating U.S. hopes of securing Pakistani support as it withdraws from neighboring Afghanistan.

The current civilian-military tensions in Pakistan center on an unsigned memo that was delivered to the Pentagon in May, requesting help for the Islamabad government in halting a possible military coup and curbing the army’s power. The memo infuriated the army, and Pakistan’s Supreme Court is investigating the document’s origin and whether it was approved by the president. The government has denied involvement.

But as pressure mounts, the elected government has repeatedly lashed out at the army, which is viewed as Pakistan’s most potent force. Last month, Gilani denounced what he called a “state within a state” and suggested that a military coup plot was in the works. Two days ago, Gilani told a Chinese newspaper that Gen. Ashfaq Kayani, the army chief, and Lt. Gen. Ahmed Shuja Pasha, the head of Pakistan’s top spy agency, had acted illegally and violated the constitution by submitting affidavits about the memo case to the court.

Pakistan’s now-former defense minister, Naeem Khalid Lodhi, was sacked by Pakistani Prime Minister Yousuf Raza Gilani on Wednesday for "gross misconduct.” (Pakistan Defense Ministry/AFP/Getty Images)

On Wednesday, Gilani fired his defense secretary, retired Lt. Gen. Naeem Khalid Lodhi, accusing him of “gross misconduct and illegal action” and of “creating ­misunderstanding between the state institutions” by not following government procedures for submitting the Kayani and Pasha affidavits. Lodhi, who was considered close to the army, embarrassed Gilani last month by submitting a statement to the Supreme Court saying that the government had no “operational control” over the army or intelligence services. He was replaced by a civilian loyal to Gilani, local media reported.

Hours earlier, the army had issued a statement denying that the affidavits filed by Kayani and Pasha were improper and noting that they were submitted through government channels. Gilani’s accusation “has very serious ramifications with potentially grievous consequences for the country,” the statement said, without elaborating.

Civilian governments and the army have often acted as dueling power centers throughout Pakistan’s 64-year-old history, and the military has usually been the victor. There have been several military coups, and no elected government has completed a full term. The weak current government has essentially ceded foreign and national security policy to the army.

Few here say that the army is gearing up for an outright takeover. But it is widely perceived as disgusted with Zardari and a government tainted by graft allegations and unable to control a free-falling economy. Some analysts contend that the military wants to oust Zardari through constitutional means and has influenced the Supreme Court’s aggressive stance in the Memogate case and other cases of alleged government wrongdoing.

On Tuesday, the court, which has in recent years become the nation’s third axis of power, reprimanded the government for defying its orders in a corruption investigation and warned that it could dismiss Gilani.

Speaking to reporters Wednesday night, Gilani said that Kayani had notified him of the army statement and that he did not protest. Gilani said that his comments to the Chinese newspaper reflected his belief in the “balance of powers” but that he had always “stood by the army.”

“The democratic process will continue,” he said.

Even amid the public salvos, backroom efforts have been underway to ease the civilian-military strains, according to officials with the ruling Pakistan People’s Party. But those officials also say that they believe the army is determined to see the memo scandal topple the government. With parliamentary upper-house elections approaching and calls for early general elections growing, analysts say the party has decided that confronting the army will win it sympathy — and Gilani, whose political capital is greater than the unpopular Zardari’s, has assumed the starring role.

Pundits on Pakistani television talk shows, which are generally deferential to the military, on Wednesday deemed that a dangerous tack. Some said that with its latest move, the government was threatening Pakistan’s nascent democracy and risked appearing to have chosen a collision course only to save Zardari.

“The army is for all purposes set to back the judiciary,” Shahzad Chaudhry, a retired vice air marshal and defense analyst, told the Dunya news network. “The government is now in a closed alley, a dark street. But it is responsible for its debacle, all the problems and the struggle for survival it is involved in.”

Lodhi’s firing sparked speculation in the Pakistani media that Gilani was moving toward dismissing Kayani or Pasha, which would require the defense secretary’s backing. Ruling-party politicians rejected that notion, suggesting that the firing was routine.

“This is all media hype, and there is no grave crisis,” said Khursheed Shah, a member of Parliament. “The government does not want confrontation with any institutions, and the country could not afford any such crisis.”

Special correspondent Shaiq Hussain contributed to this report.