Thousands of Kosovo's opposition supporters have called for the government to resign on the eighth anniversary of the country's declaration of independence, accusing it of violating the country's constitution in reaching deals with Serbia and Montenegro.

Opposition supporters came from all over the country to Pristina for the rally on Wednesday.

Al Jazeera's Stefan Goranovic, reporting from the capital, said more than 15,000 were estimated to have taken part in the event.

"Opposition representatives are asking for the immediate resignation of Prime Minister Isa Mustafa and the Foreign Minister Hashim Thaci," our correspondent reported.

The opposition rejects a deal between Kosovo and Serbia reached last year, giving more powers to ethnic Serbs in Kosovo. In December, the Constitutional Court decided that part of it was not in line with the constitution.

The opposition also rejects a border demarcation deal with Montenegro and has called for a referendum or a new election. They have attempted to disrupt the work of parliament with tear gas, pepper spray and whistles.

Shouting anti-government slogans, most of the participants in Wednesday's protest held Albania's red-and-black national flag at the Skanderbeg Square. Far fewer Kosovo flags were visible, along with a few US and German flags.

"Kosovo will not allow itself to be led by people who have violated the constitution, its sovereignty," said Visar Ymeri, leader of the main opposition Self-Determination Movement party.

Ymeri set a February 27 deadline for the government to resign and declare a new election, or "our protests will not stop". The rally participants dispersed peacefully.

Another protest was called for Friday when parliament may start procedures on electing a new president.

Deputy Prime Minister and Foreign Minister Hashim Thaci of the Democratic Party of Kosovo is the only self-declared candidate so far.

"In a normal situation, there can be no presidential election when the people insist the government shouldn't stay in office for a single minute (longer)," Ymeri said.

The government accuses the opposition of trying to come to power through violence.

Earlier on Wednesday, the government held a ceremony to celebrate the eighth anniversary of the 2008 unilateral independence declaration with a military parade.

"Such a government has a clear mandate. It has the legitimacy to serve the citizens who trusted it with the majority of votes in a democratic process accepted by the whole political spectrum in Kosovo," Prime Minister Isa Mustafa said.

Kosovo's Western backers have denounced opposition-led violence, calling on the opposition to resolve the political crisis in parliament.

Kosovo's independence has been recognised by 111 countries, including the US and major European Union nations. But it is rejected by Serbia, with support from Russia, which has blocked Kosovo from becoming a UN member.

Kosovo and Serbia are holding EU-mediated talks to try to overcome their differences.