KIEV, Ukraine (CNN) — Ukraine's military forces urged the President on Friday to act to restore stability, saying that a further escalation of the political unrest in the country threatens its territorial integrity.
President Viktor Yanukovych must take "immediate measures to stabilize the situation," said a statement posted by the country's Defense Ministry on Friday.
In an interview with Russian state news agency Itar-Tass on Sunday, Ukrainian Defense Minister Pavel Lebedev said that Ukrainian military forces would not interfere in the country's current political unrest.
"The army will abide strictly by the constitution and laws of Ukraine that set clearly its role, functions and tasks, including use of armed forces," Lebedev said.
Yanukovych on Thursday defended his government's handling of the political crisis, saying that it had "fulfilled all its obligations" and that opposition leaders were stoking people's anger for their own gain.
Earlier in the day, Yanukovych's office said he was out on sick leave after an "acute respiratory disease accompanied by fever."
The country's Parliament approved an amnesty bill for anti-government protesters in an extraordinary session Wednesday.
But the opposition has rejected the measure, which comes into force only if protesters vacate seized government buildings and unblock streets and squares.
Protesters have remained on the icy streets of the capital, Kiev, in defiance of the amnesty law.
Former Ukrainian President Viktor Yushchenko told CNN's Christiane Amanpour on Thursday that the Ukrainian opposition does not fully control the street protests that have shaken the country.
The opposition, he said, has not provided a "comprehensive pact" that would satisfy the demands of the protesters.
The opposition is concerned about "the fight for power," but less with "the strategic course of the country," he said, speaking through a translator.
'Respect his people's wishes'
Protesters have camped out on Kiev's Independence Square, or Maidan, since November, when the President reversed a decision to sign a long-awaited trade deal with the European Union and turned instead toward Russia.
The protests turned violent after Yanukovych's party rammed a controversial anti-protest law through Parliament two weeks ago. At least four protesters have been killed. Police officers have also been killed and injured in the clashes.
Parliament voted to annul the anti-protest law in a special session Tuesday, in what the opposition said was a first step toward meeting its demands. Prime Minister Mykola Azarov and his Cabinet resigned shortly afterward.
Opposition politicians have called for Yanukovych also to stand down, but he has not given any indication he will do so.
Speaking at a joint news conference in England on Friday with French President Francois Hollande, British Prime Minister David Cameron appealed for a peaceful resolution to the crisis.
"We are concerned about the violence in Ukraine. The repeal of restrictions on fundamental freedoms was a step in the right direction, and we urge President Yanukovych to respect his people's wishes and put his country back on a path to a more stable and secure European future," Cameron said.
"On Ukraine, we are calling to an immediate dialogue without violence," Hollande said.
There have been tensions between Russia and the European Union over developments in Ukraine, with each side accusing the other of interference.
Russian President Vladimir Putin, who agreed to a $15 billion loan deal with Yanukovych after his U-turn on the EU agreement, has denied exerting undue influence on the former Soviet republic.
CNN Pierre Meilhan and Mick Krever contributed to this report.