Jaroslaw Kaczynski (r) was sworn in by his brother last week

Jaroslaw Kaczynski, who heads the conservative governing Law and Justice Party, won by 240 votes to 205.

He was appointed to the post by identical younger twin President Lech Kaczynski last week.

The result means that Poland is the only country in the world to have twins holding the top two political jobs.

"I'm happy. We will now be able to get to work. There are many things to get done in Poland," Jaroslaw Kaczynski said of parliament's approval, which is needed before a prime minister can officially take up his duties.

In a policy speech before the vote, he said his priorities would be to fight corruption, reform public finances and build more highways and homes.

He said Poland was committed to the European Union, but insisted Brussels must respect the country's traditional Catholic values.

He also reaffirmed Poland's alliance with the US and indicated Polish troops would not be pulled out of Iraq any time soon. "Poland is not a nation of deserters," he said.

The government's opponents have accused the twins of badly neglecting foreign policy and undermining Poland's standing within the European Union.

Limited appearances

Jaroslaw Kaczynski was widely expected to take the job last September, when his party won parliamentary elections.

But at that time, Lech was running for president and Jaroslaw argued the public would not stomach identical twins running the country.

Now, with Lech - the younger by 45 minutes - safely in office, Jaroslaw has changed his mind, the BBC's Adam Easton in Warsaw says.

The president did not attend the speech, and the twins are limiting their appearances together.