"Soon a jet plane will have to be kept on standby in Minsk," Radek Sikorski said, referring to the capital of Belarus. "You are losing ... sooner or later you will have to flee your own country, your own people."
Sikorski spoke at international donors' conference in Warsaw where governments pledged millions in aid for the democratic opposition in Belarus, which faces censorship and the constant threat of arrest under President Alexander Lukashenko.
The conference brought pledges of euro87 million ($120 million) in aid through 2013, most of it new contributions, Sikorski said.
"The people in Belarus have the right to have a reasonable government," he told the conference, attended by 200 representatives from the United States, Canada, European governments and pro-democracy groups.
Lukashenko, often called "Europe's last dictator," has ruled the 10-million nation with an iron hand for more than 16 years. He has kept industry under Soviet-style state control and suppressed opposition with police raids and pressure, but his fiery populism and efforts to maintain a Soviet-style social safety net have kept him popular with the working class and the elderly.
In December, mass election protests in Belarus were brutally dispersed and opposition candidates arrested following a presidential election that international monitors regarded as fraudulent. Lukashenko was declared the winner, claiming almost 80 percent of the vote.
The European Union's enlargement commissioner, Stefan Fuele, said the EU would quadruple its previous aid to the families of those facing repression in Belarus: expelled students, independent media outlets and opposition organizations. That raises EU aid to euro15.6 million ($21 million) annually through 2013.
The U.S. government pledged to boost its annual aid contribution by 30 percent to $15 million. U.S. Deputy Assistant Secretary of State Daniel A. Russell also said Washington was expanding its list of Belarus officials under travel restrictions.
Washington is responding "in concert with Europe," Russell told a news conference. "The message to the government in Minsk should be that it is facing a concerted effort."
Lukashenko's grip on power appeared shaken before December's election amid a falling out with his main sponsor and ally, Russia. Moscow, however, hasn't followed up on its threat to stop supplying Belarus with the cheap energy that keeps its economy afloat and recently warned the West against trying to isolate Belarus, a former Soviet republic.
Poland has taken a leading role in trying to promote democracy in Belarus, considering it a matter of strategic importance to have democracies along its eastern border. Also, many of Warsaw's leaders are former democratic activists who helped topple Poland's Soviet-backed communist regime in 1989.