President Bakiev had earlier promised to "personally" submit his proposals to the legislature.
Instead, it was his representative in parliament, Alymbay Sultanov, who brought the proposals in the form of a "draft bill on changes and additions" to the existing constitution.
Addressing reporters afterwards, State Secretary Adakhan Madumarov said Bakiev's proposals aim to create a mixed presidential-parliamentary form of government.
Madumarov said that under the amended constitution the legislature would have greater powers, including the right to appoint the prime minister. He also said the changes would restrict the president's ability to dissolve parliament.
"[The president is proposing] a consensual form of government," he said. "I think that all two, three, four sides involved [in the discussion], as well as some political parties, have agreed that Kyrgyzstan should have a presidential-parliamentary form of government. This is what has been sent [today] to parliament for reviewing."
Bakiev's opponents reacted harshly to the initiative, saying it would only deepen the ongoing political crisis.
Edil Baisalov, one of the leaders of the For Reforms opposition movement, accused Bakiev of "cheating" and "pulling the knot tighter" on his polilical foes.
Opposition Being Undercut By Bakiev?
Another For Reforms leader, lawmaker Azimbek Beknazarov, voiced frustration at Bakiev's initiative.
He said that by offering to amend the existing constitution instead of proposing a new draft of the fundamental law, Bakiev is seeking to cut the ground from under his opponents' feet.
According to Beknazarov, only the president can amend the existing constitution and parliament can only reject or approve his proposals.
Addressing protesters gathered in front of the building that hosts the presidential administration and the government's headquarters -- known as the White House -- opposition lawmaker Omurbek Babanov accused the president of foul play.
Protesters rallying on November 6 (RFE/RL)
"The president has submitted a project that is worse than the current constitution," he said. "That's how he's listening to us! What he proposes is a super-presidential constitution. We won't let [him] do that. Bakiev should go!"
Another opposition leader, former cabinet minister Almazbek Atambaev, expressed similar criticism.
Strengthening, Not Diminishing
"Unfortunately, instead of bringing a new draft constitution that would restrict the rights of [his] family clan, President Kurmanbek Salievich Bakiev today submitted a totally different draft," he said. "His draft makes the existing constitution even worse. It will make the country even more dependent on one single individual who, as we see, is surrounded by not very recommendable people. It is a great misfortune for the country."
Parliament Speaker Marat Sultanov also dismissed the president's proposals.
"We thought the president would come out with democratic proposals that would restrict his powers," he said. "But they restrict his prerogatives with regard to only one thing, that is the nomination of the prime minister. For the rest, it strengthens the presidential powers."
Following the news that Bakiev had submitted to parliament proposals that did not meet the opposition's demands, the number of protesters swelled outside the White House.
RFE/RL's Kyrgyz Service reports that by mid-afternoon there were at least 10,000 people on Bishkek's central Alatoo Square, which abuts the building.
As tensions rose, presidential administration head Myktybek Abdyldaev appeared before the crowd and read out a presidential decree removing acting Interior Minister Osmanali Guronov from office.
Abdyldaev said the president had put Guronov's deputy, Omurbek Subanaliev, temporarily in charge of the ministry. Addressing the demonstrators, Subanaliev pledged to not use force against them.
He also vowed that Bakiev will sack Bishkek police chief Moldomusa Kongantiev, the brother of Prosecutor-General Kambaraly Kongantiev.
Kongantiev's removal was one of the demands of the opposition.
Some opposition leaders, however, dismissed the reshuffle as a tactical move by Bakiev and his supporters to buy time.
For Reforms leader Temir Sariev said the crowd would not disperse until the president leaves office.