Ashton has spent much of the week in Kiev talking with Ukrainian President Viktor Yanukovych. Ukraine descended into chaos when lawmakers suspended efforts to sign free trade and association agreements with the European Union though Ashton said she had assurances from Yanukovych he was eager to sign the measures.
"I want him to do so and I believe that doing so swiftly is the best way to also address the short term economic challenges, which he says are at the forefront of his mind at the present time," she said in a statement published Thursday.
The Yanukovych administration said the November decision was made to protect Ukraine's economic interests with Russia.
Ukraine is a former Soviet republic.
Western governments have expressed frustration with a decision in Ukraine to send police to break up ongoing protests in Kiev. U.S. State Department spokeswoman Jen Psaki said during a press conference Wednesday sanctions were under consideration.
"All policy options, including sanctions, are on the table in our view," she said.
Ashton said European leaders were developing proposals for an independent investigation into the violence.
"It's so important when violence happens ... that there is a chance to examine what occurred, to bring people to justice and to ensure that it does not happen again," she said.