The former Soviet republic has been convulsed by unprecedented demonstrations against President Alexander Lukashenko since he was returned to power in a disputed August 9 election and launched a brutal crackdown.
"She gave us an account of the events in Belarus", EU foreign policy chief Josep Borrell told reporters, after a breakfast meeting with Tikhanovskaya and the ministers.
Brussels is yet to approve a list of 40 Belarusian officials who are set to be hit with travel bans and asset freezes.
The strongman, who has ruled Belarus for more than a quarter of a century, has responded to the protests with a security clampdown and turned to his longstanding ally Russian Federation for help.
Russian foreign ministry spokesperson Maria Zakharova also criticized the European Union for inviting Tsikhanouskaya to the ministerial meeting as well as for considering sanctions against Minsk, saying Brussels was trying to "rock the boat" in Belarus.
"EU leaders have reasons not to push sanctions but I asked them to be more courageous", Tsikhanouskaya, who fled to Lithuania after the election, told reporters after meeting foreign ministers. Svetlana Tikhanovskaya, the opposing candidate for the elections, fled to Lithuania for the safety of her children.
"We did a lot to manage with this situation by ourselves, with only the strength of the Belarusian people, but now I understand that we need exterior help", she said, speaking in English. But he also acknowledged the paralysis was damaging for the EU's image.
"I ask you to work together for a free, fair and transparent election, in accordance with worldwide standards and under the supervision of local and global observers", Tikhanovskaya said, highlighting that "the new Belarus" will be based on the rule of law and will not tolerate state violence and falsified elections.
Lukashenko has dismissed opposition calls for his resignation and sought help from Russia's President Vladimir Putin, who has promised law enforcement backup if needed and a $1.5 billion loan.
On Friday she urged the global community to respond to abuses in Belarus "in the strongest terms" in a video appearance at the UN Human Rights Council in Geneva that was repeatedly interrupted by the Belarusian ambassador. But sanctions require agreement among all 27 member states, and the Belarus issue has become entangled in a debate over separate sanctions against Turkey, sought by Cyprus in a dispute over energy resources.
She also asked for Europe's solidarity with the Belarusian people, and support to civilians and media organisations, for a criminal investigation for human rights crimes in the country, and for a review of EU's partnerships with state organisations close to Lukashenko.
However, he said, "our reaction to any kind of violation of our core basic values and principles can not be a la carte". It needs to be consistent.
The matter will now be considered by EU leaders at a summit in Brussels on Thursday and Friday, and Borrell said he wanted the sanctions signed off before the next meeting of foreign ministers in October, warning that "the credibililty of the European Union" depended on it. "If workers stop their operation, that would be huge heat on the system", he said, predicting then "Lukashenko will have to agree on the dialogue" with the opposition Coordination Council proposed by Tsikanouskaya.