New Polish PM Kaczynski sworn in by President

WARSAW, July 14 (Reuters) Jaroslaw Kaczynski was sworn in as Poland's prime minister by his twin brother, President Lech Kaczynski, in a ceremony today, solidifying the Kaczynski family's grip on power in the EU's biggest new member.

The Kaczynskis become the world's only twins to hold a nation's top two executive posts.

Veterans of the anti-communist Solidarity movement, the Kaczynskis mix conservative social views, tough line on corruption, belief in state intervention in the economy and scepticism of deeper European integration.

Lech Kaczynski said his brother's nomination marked a fresh start for a government often criticised for mishandling foreign relations and drifting on domestic policy.

''We have to implement plans to build a properly functioning country, without corruption, a country helpful toward its citizens, to build an independent Poland within the EU,'' President Kaczynski said.

Jaroslaw Kaczynski, head of the ruling conservative Law and Justice party, replaces fellow party member Kazimierz Marcinkiewicz, who resigned in a surprise move last week.

Prime Minister Kaczynski said his first objective was to pass new legislation, although he did not elaborate on what bills would be given priority.

''I'm convinced Poland will be better off if our programme is implemented,'' he said. ''It is an opportunity, an opportunity to define our place in the EU.'' Financial markets, initially jittery over the cabinet reshuffle, were calmed earlier this week when Kaczynski said he would stick to budget deficit ceiling set by Marcinkiewicz and promised to make public finance reform a priority.

His party's platform promises a crackdown on corruption and more efficient courts.

Kaczynski kept Marcinkiewicz's team in place, with the exception of bringing in a new finance minister, Stanislaw Kluza, a former bank economist also sworn in today.

The new cabinet is expected to win majority backing in a confidence vote in parliament scheduled for Wednesday.

Kaczynski decided to replace Marcinkiewicz following growing tensions over appointments to top state posts.

Lech Kaczynski, former Warsaw mayor, won presidential elections in October after his Law and Justice won parliamentary polls in September.

REUTERS PKS RN1933