ASTANA, Kazakhstan — This capital city has been abuzz for weeks with the latest political news: Soon there will be politics. After an election scheduled for Sunday, Kazakhstan’s Parliament will be guaranteed, under a new law, to consist of more than one political party.

That might not generate much interest elsewhere, but, for the past five years, every elected member of the Kazakh lower chamber was a member of the pro-government Nur Otan party, making for dull debates.

The government is praising the change to a multiparty system as a step toward liberalization in Kazakhstan, a United States ally considered important to world oil markets as a major producer outside of the Middle East. In comments reported by his press service when the election was announced in November, President Nursultan Nazarbayev said, “Society needs a multiparty system.”

Since the Arab uprising, speculation has swirled over whether similar protests could spread to the 50 million or so mostly Muslim residents of former Soviet Central Asia; in four of the five successor states — Kazakhstan, Uzbekistan, Turkmenistan and Tajikistan — ossified authoritarian leaders have ruled unchallenged for decades.