Poland also wants to forge closer ties with the US, demanding a bilateral relationship similar to the one between the US and Britain.

The Polish government's desire for such a hard bargain with the United States is also a response to the concerns of the Polish people.

According to opinion polls, the majority of the Polish people oppose the deployment of the missile shield in the country, saying it would place Poland in a dangerous situation.

The Russia element

Another element that may deter Poland from signing a deal with the US is Russia's vehement opposition to the missile shield system.

Russia has been arguing that the system would threaten Russian national security and pledged to carry out reprisals should it be deployed in eastern Europe.

Bilateral relations between Russia and Poland had been tense since November 2005, when Russia imposed an embargo on meat products from Poland, accusing Poland of presenting false veterinary certificates.

Poland responded by vetoing an EU proposal to launch negotiations with Russia on a new partnership deal.

With Tusk elected as Polish Prime Minister in November 2007, the Polish government said on several occasions it was willing to improve ties with Russia and lifted its veto on the EU-Russia partnership talks in mid February.

But despite signs projecting a better relationship, Poland may still face pressure from Russia on the missile shield issue, analysts said.