Belarusian President Alexander Lukashenko on Saturday issued an appeal to long-term ally Russia as he faced growing pressure to step down following a disputed election that has triggered protests at home and condemnation abroad.
Lukashenko is grappling with the biggest challenge to his 26-year rule as tens of thousands of people have taken to the streets accusing him of rigging last Sunday's presidential election, and calling for him to step down.
He suggested that the impact of the protests might spill beyond Belarus's borders.
"There is a need to contact (Russian President Vladimir) Putin so that I can talk to him now, because it is not a threat to just Belarus anymore," Lukashenko said, according to state news agency Belta.
"Defending Belarus today is no less than defending our entire space, the union state... Those who roam the streets, most of them do not understand this."
Citing Belarusian media, Interfax said Lukashenko had discussed the situation with Putin in a telephone call. The Russian news agency gave no details.
The European Union is gearing up to impose new sanctions on Belarus in response to a bloody crackdown in which at least two protesters have been killed and thousands detained, while the leaders of Estonia, Latvia and Lithuania called on Belarus to conduct new "free and fair" elections.
Opposition presidential candidate Sviatlana Tsikhanouskaya, who fled to neighbouring Lithuania on Tuesday, has called for more protests and an election recount.
Crowds gathered in Minsk again on Saturday to lay flowers where one of the protesters was killed this week.
Russia sees Belarus as a strategic buffer against NATO and the EU, but ties between the two countries had been under strain before the election.
Moscow scaled back financial support to Minsk and Lukashenko rejected Russian calls for closer political and economic union.
Lukashenko has accused the protesters of being in league with foreign backers, and warned Belarusians to stay at home to avoid becoming "cannon fodder".
Moscow this week also accused unnamed countries of "outside meddling" in Belarus.
Russia has been wary of unrest on its borders since governments fell in Georgia's 2003 Rose Revolution, Ukraine's 2003-04 Orange Revolution and Kyiv's 2014 Maidan protests - events in which it says the West backed the protesters.