The Polish Prime Minister, Donald Tusk, visits Brussels on Tuesday - his first major diplomatic move since he formally took office last month.
Donald Tusk wants warmer ties with EU neighbours and Russia
He has promised to improve ties with the EU and fellow member states.
Mr Tusk is due to meet the European Commission president, Jose Manuel Barroso, and the Nato Secretary General, Jaap de Hoop Scheffer.
His predecessor Jaroslaw Kaczynski was involved in a series of disputes, particularly with Germany.
In one notorious remark on Poland's voting rights, Mr Kaczynski suggested that the EU should take account of the six million deaths suffered by his country during six years of Nazi German occupation in World War II.
The new prime minister has already visited Lithuania in an attempt to restore relations which soured over a planned Lithuanian nuclear plant, which is due to provide power to all the Baltic states as well as Poland.
Mr Tusk is also working to mend ties with Russia which faltered when Moscow slapped a ban on Polish meat. Poland responded by blocking partnership talks between Russia and the EU.
The two countries will have their highest-level talks for more than a year when the Polish Foreign Minister, Radek Sikorski, meets his opposite number Sergei Lavrov in Brussels on Thursday.
The previous government in Warsaw was keen to be part of the planned US anti-missile defence shield, allowing a missile interceptor base on its territory.
Mr Tusk's government says it wants to reassure Moscow about the project while working in partnership with its Nato and EU partners.
Mr Sikorski may himself have to adopt a more diplomatic tone than in the past.
Last year, as defence secretary, he condemned Germany for failing to consult Poland about a major gas pipeline project with Russia.
"That was the Locarno tradition, that was the Molotov-Ribbentrop tradition," he said, referring to the notorious Nazi-Soviet pact to divide Poland.