Minsk (CNN)Embattled Belarusian leader Alexander Lukashenko has been inaugurated as President, state media reported, as protests continue over his hotly-disputed election win.
The country's state press service released images of the unannounced ceremony, which took place in the capital, Minsk, on Wednesday.
The embattled Belarusian president assumed office during a ceremony at Minsk's Palace of Independence. No prior notice was given of the event, which took local journalists and opposition activists by surprise.
Opposition politicians described the ceremony as a "thieves' meeting" and a "farce."
The opposition Coordination Council, set up to facilitate a transfer of power, urged members of the international community Wednesday to support its members and denounce Lukashenko's appointment.
"This morning Alexander Lukashenko appointed himself the President of the Republic of Belarus...the Belarusians did not vote for him in the election, though this farce can hardly be called an election," the Board of the Coordination Council said Wednesday in a statement.
"We call on the European Union, Great Britain, the USA, Canada, China, [and] Russia to take a clear position on recognising Lukashenko [as] illegitimate and to consider recalling your ambassadors for consultations," the statement added.
The US said Wednesday that it rejected the legitimacy of Lukashenko's win.
"The United States cannot consider Alyaksandr Lukashenka (Alexander Lukashenko) the legitimately elected leader of Belarus," a US State Department spokesperson said in a statement to CNN.
"The elections August 9 were neither free nor fair. The announced results were fraudulent and did not convey legitimacy."
Lukashenko was declared the landslide winner of the vote in August, but critics have publicly accused him of rigging the poll, and have since disappeared from the country.
Tens of thousands of protesters have also taken to the streets in mass demonstrations across Belarus for weeks.
Opposition candidate Svetlana Tikhanovskaya, who is coordinating the protests from exile in Lithuania, said that "this so-called inauguration is, of course, a farce."
"Lukashenko's attempt to preserve his legitimacy only points to the fact that his previous authority has ended, but Belarusian citizens did not give him a new mandate," Tikhanovskaya posted on her Telegram feed.
Another opposition politician, Pavel Latushko, accused Lukashenko of holding a "special operation on self-inauguration."
"Under the protection of riot police, in the atmosphere of secrecy, in a narrow circle of hastily brought officials. Where are the jubilant citizens? Where are the diplomatic corps? To be honest, it looks more like a thieves' meeting for the coronation of another thief-in-law," Latushko wrote on social media.
Lukashenko, who has been in power since 1994, assumed the office for his sixth consecutive term after taking an oath, state press service Belta reported.
"Assuming the office of the President of the Republic of Belarus, I solemnly swear to faithfully serve the people of the Republic of Belarus, respect and protect the rights and freedoms of man and citizen, observe and protect the Constitution of the Republic of Belarus, sacred and conscientiously fulfil the high duties entrusted to me," the oath read.
Several hundred people were invited to Wednesday's ceremony, according to the press service.
Belta said that senior officials, deputies of the House of Representatives, heads of state bodies, scientists, culture and sports figures were invited.
Over recent weeks, Lukashenko and the Belarusian state security apparatus has been forcibly removing from the country or detaining leading opposition figures.
The Coordination Council reiterated its willingness to negotiate with authorities on Wednesday.
The opposition body also called on citizens to continue mobilizing against the government.
"We are ready to start immediate negotiations with the Prime Minister of Belarus and with the Chairmen of commissions at the Chamber of Representatives about setting the date of a new election and about temporary governance during the transition period," the Coordination Council said.
"We support the infinite peaceful civil disobedience, ignoring any and all instructions from the illegal authorities, peaceful actions in the streets of cities and towns," it added.
Meanwhile, demonstrations have continued across the country, particularly at weekends. On Saturday, 430 people were detained in protests across the country, according to the Interior Ministry. Of those, 415 were in the capital Minsk. Some 385 people had been released as of Sunday morning, the Ministry said.