The Supreme Rada ordered Defense Minister Anatoliy Hrytsenko and Foreign Minister Borys Tarasyuk, both from the pro-presidential Our Ukraine bloc, to present reports on their activities by next week.
Friday's decision comes a day after the parliament suspended the interior minister, a supporter of Western-oriented President Viktor Yushchenko, over a probe into alleged corruption cases in his ministry.
On Wednesday, parliament approved the resignations of the justice and culture ministers, two of the four Cabinet members from Our Ukraine, who announced plans to step down October 9, in line with their party's decision to go into opposition and form a shadow Cabinet.
"Delivering a report will not be easy for them," said Yevhen Kushnarev, a deputy head of the ruling Party of Regions faction. Several ministers have in effect formed their own coalition in the government, and are criticizing decisions that have already been made, he said.
"We will demand that these ministers carry out the policies of the anti-crisis coalition, as one cannot have his legs in the government and his head in the opposition," Kushnarev said.
The parties of the pro-Russian 'anti-crisis' coalition (the Party of Regions, the Socialists and the Communists) formed after the pro-Western 'Orange Coalition' collapsed earlier in the year, have dominated parliament since the Party of Regions leader, Viktor Yanukovych, was appointed premier in August
Both political sides signed a national unity agreement before the government's appointment on securing Yushchenko's key pro-Western policy goals, including NATO accession and eventual EU membership. But the pro-Russian governing coalition has continued to drag its feet on the president's policy drives and has failed to form a grand coalition with Our Ukraine.
Vyacheslav Kirilenko, an Our Ukraine parliamentary faction member, said Thursday the move against Interior Minister Yuriy Lutsenko was "political revenge." He also predicted probes against Hrytsenko and Tarasyuk.
"I am sure that similar decisions will be made tomorrow with respect to other 'Orange' ministers in Yanukovych's Cabinet," he said, referring to the late 2004 mass protests known as the "Orange Revolution," which swept Yushchenko to power.