A senior U.S. diplomat has arrived in the Ukrainian capital to try to help find a resolution to the protests and political crisis that have gripped the country for more than two months.

The U.S. Embassy says Assistant Secretary of State Victoria Nuland is to meet President Viktor Yanukovych and leaders of the opposition during her two days in Kiev.

The trip comes amid growing frustration over parliament's failure to enact constitutional reforms and an amnesty for protesters. The legislature met three days this week, but produced no results and on Thursday adjourned until next week.

About 2,000 demonstrators on Thursday marched toward the parliament building carrying a huge banner reading "We are tired of waiting." Participants said they are ready to resume clashes with police if parliament's inaction continues.