Ukraine is under fire for not cooperating with the Swiss investigation into whether a key Yatsenyuk ally, lawmaker Mykola Martynenko of the prime minister’s own People’s Front party, accepted a bribe of 30 million Swiss francs for an agreement to supply equipment to Ukraine’s nuclear power stations. The Swiss investigation has dragged on for two years. Yatsenyuk said it’s not his responsibility. Moreover, he told Politico that he refused to order a party or parliamentary investigation into the matter because his ally “strongly denies all these allegations.”

Really? Since when are criminal suspects able to evade investigation because they proclaim their innocence? This is akin to not investigating ex-President Leonid Kuchma because he swears he had nothing to do with the murder of journalist Georgiy Gongadze in 2000.

In this one damning passage alone, Yatsenyuk cast his lot with forces suspected of corruption rather than those trying to find the truth, with those who want to keep conflicts of interest and insider dealings as the standard way in which Ukraine conducts its business, rather than those trying to impose rule of law.

It is hard to see how much longer he can stay in office with such taints, even harder to imagine how he can tell the world with a straight face he is interested in fighting corruption if he doesn’t take such allegations against his allies seriously. It is doubtful that Yatsenyuk’s Western backers will continue to support this prime minister. Most Ukrainians have already given up on him.

Yatensyuk appears to see himself as a victim of anyone who disagrees with him – the media, the prosecutor, the judiciary, Odesa Governor Mikheil Saakashvili and Western donors who justifiably insist on a genuine clampdown on graft.

It’s unfortunate because his government has made real achievements. The elimination of energy mogul Dmitry Firtash and other intermediaries from the gas sector is one of them. Also, several ministers are making progress in modernizing government and making it work more transparently in numerous ways. This is to their credit and to his, even though many changes were part of Western aid conditions. But Yatsenyuk’s petulance and no-show, bordering on obstructionist, attitude on fighting corruption will undermine all progress.

“The Swiss government didn’t contact the Ukrainian government. The government has nothing to do with the prosecutor’s office, nor the judiciary,” Yatsenyuk told Politico. He left out the police, over which he does have influence. Interior Minister Arsen Avakov commands 150,000 law enforcers and is a leading member of Yatsenyuk’s party. He also left out the fact that, indeed, the prime minister has great influence in how prosecutors, police and judges are paid through the state budget, appointments and conflict-of-interest laws that could help ensure an independent yet effective judiciary.

Yatsenyuk last month announced support for a dramatic anti-corruption proposal to fire all of the nation’s 9,000 judges, curb prosecutorial powers and set up a state investigative agency. But it has to go through parliament and, to do so, that requires lobbying, planning and strategy, not just a fleeting pronouncement in front of TV cameras.