The parliamentary session began well into the night and lasted less than an hour.
Parliament speaker Marat Sultanov announced the adoption of the new fundamental law after two swift successive readings.
"There are, in the history of a state, some important moments. Our only demand is that Bakiev quickly implement the reforms. The president must do that; he must behave like a responsible politician."
"Now dear colleagues, I suggest that you vote this proposal -- sorry, this constitution -- in the second reading," he said. "Please, proceed!...The [constitution] is adopted by 65 'yes' votes!"
An RFE/RL Kyrgyz Service correspondent reported from the parliament building that 68 of the Jogorku Kenesh's 71 members had registered before the vote. The three remaining parliamentarians apparently failed to vote quickly enough.
Provided President Kurmanbek Bakiev approves it, the new constitution should make Kyrgyzstan the first Central Asian country to have strong parliamentary checks and balances on the powers of the president.
Pro-government parliamentarian Akmatmek Kedilbekov welcomed the vote as a milestone in Kyrgyzstan's post-Soviet history.
Both Sides Satisfied?
"It is the nation that won," he said. "Both the president and the opposition won!"
Shortly before the session opened, State Secretary Adakhan Madumarov had appeared before the lawmakers to tell them that Bakiev had finally approved the draft and signed the procedural amendments that were needed for the adoption of a new constitution by the legislature.
The amendments had been passed by the parliamentarians early in the morning, but Bakiev did not sign them until late in the evening.
Asked earlier by reporters why it was taking the president so long, Madumarov said: "Long? You know how heavy those legislative procedures are. Every single dot, every single comma must be examined by legal experts and they must then give their conclusions to the president. This is the norm for all [draft] laws, not only for this one. But rest assured that the president will sign it today."
The new constitution was drafted on November 7 by a so-called conciliation commission made up of pro-government and opposition lawmakers.
Mixed Form Of Government
It aims to establish a mixed parliamentarian-presidential form of government.
Parliament speaker Sultanov and opposition lawmakers had said during the day that Bakiev wanted to add some amendments before sending the draft to the legislature.
Reports suggest lawmakers agreed on at least two of Bakiev's demands -- that his name appears as one of the new constitution's co-authors, and that the president retains the right to appoint local judges.
The original draft said the president would have to surrender control over the National Security Service (SNB) and the Prosecutor-General's Office and that the presidency would lose its power to dismiss the heads of the Central Election Commission and the Accounting Chamber without getting legislative approval.
It also said the president would no longer have the right to appoint the prime minister and that that prerogative should be transferred to the party that has the most seats in a parliament, whose membership should be increased to 90 from a current 75 (four seats are currently vacant).
"With regard to the formation of the government, if a party wins more than 50 percent of the seats in parliament, one of its representatives will automatically be prime minister," opposition lawmaker Azimbek Beknanarov told RFE/RL's Kyrgyz Service. "If no party has a majority, then the president will entrust the party that garnered the most votes with the task of choosing a prime minister. The prime minister will form a government that will be approved by the president."
The adoption of the new law is expected to end a months-long standoff between Bakiev and his political foes. Opposition leaders have vowed to send their thousands of demonstrating supporters home as soon as the new fundamental law is adopted.
In comments to RFE/RL earlier today, opposition lawmaker Temir Sariev urged Bakiev to end the ongoing poiltical crisis by accepting the compromise version of the constitution.
"If we fail to adopt a new constitution and send people home by this evening, then we may find ourselves in a difficult situation," he said. "The president had to understand that. There are, in the history of a state, some important moments. Our only demand is that Bakiev quickly implement the reforms. The president must do that; he must behave like a responsible politician."
Opposition protesters have been demonstrating in Bishkek since November 2 to demand that Bakiev agree on constitutional and other reforms -- in accordance with pledges he made before being elected last year -- or resign.
After parliament passed the new constitution, opposition lawmaker Melis Eshimkanov remained on Bishkek's central Alatoo Square with several hundred supporters to demand Bakiev's resignation.
As part of the compromise reached on November 7, Bakiev should stay in office until his term expires in 2010. The agreement also said that both the current parliament and Prime Minister Feliks Kulov should remain in place until that date.
(RFE/RL Kyrgyz Service correspondents Kubat Otorbaev and Aman Japarov contributed to this report from Bishkek.)