The United States, the European Union and Canada have thrown financial and diplomatic support behind the leadership that took power in Kyiv after the 2014 Maidan protests ousted the Kremlin-backed President Viktor Yanukovich.
But perceived backsliding on reform commitments has delayed billions of dollars in loans from the International Monetary Fund and tested the patience of Western countries even as Kyiv pushes for closer EU integration and possible membership.
The United States and EU have homed in on concerns that vested interests are trying to undermine the independence of the anti-corruption bureau known as NABU, which was set up after the Maidan protests and has been at loggerheads with other law enforcement bodies.
One recent episode had the General Prosecutor's office unmasking an alleged sting operation being carried out by NABU against suspected corruption in the migration service. It said NABU had overstepped the law.
General Prosecutor Yuriy Lutsenko told parliament he wanted to address issues around 'the relationship between various law enforcement agencies that causes public outrage and rather harsh statements by our strategic international partners - the U.S. and the EU.'
He denied his office was at war with NABU, saying NABU officers must face the legal consequences if they commit offenses.
'Our normal cooperation does not mean that the General Prosecutor's office can ignore signs that laws have been broken,' Lutsenko said.
Earlier Wednesday, NABU tweeted thanks to international backers for their support, posting statements released this week by the U.S. Department of State and the EU.
The U.S. State Department said on Monday that recent events in Ukraine, including the disruption of a high-level corruption investigation and the arrest of NABU officials, raised concerns about its commitment to fighting corruption.
'These actions ... undermine public trust and risk eroding international support for Ukraine,' a spokeswoman said.
The EU on Tuesday night urged that the work of anti-corruption institutions 'must not be undermined but reinforced.'
Britain's Ambassador to Kyiv, Judith Gough, on Wednesday cited a survey showing corruption within state bodies was the top issue for Ukrainian voters.
'Surely tackling corruption is a vote winner, rather than undermining institutions active in the fight against corruption?' she tweeted.