MADRID, March 6, 2008 (AFP) - A Basque nationalist party which may hold the balance of power after this week's Spanish general election offered Socialist Prime Minister Jose Luis Rodriguez Zapatero a pact Thursday.

Inigo Urkullu, head of the moderate Basque Nationalist Party (PNV), said he wanted to 'extend his hand' to Zapartero ahead of Sunday's poll to 'arrive at a pact that sets the basis for a solution to the Basque political conflict'.

The last published polls of voting intent gave Zapatero's Socialists a lead of about four percentage points over the conservative opposition Popular Party led by Mariano Rajoy.

The findings indicate the Socialists will once again come short of an absolute majority in parliament and will depend on smaller parties, including possibly Basque and Catalan nationalists, to form a government.

In the outgoing 350-member parliament, Zapatero was 12 seats short of an absolute majority.

He has governed for the past four years with the support of the Republican Left of Catalonia (ERC) separatist party, which has eight seats, and the green and communists of the United Left coalition, which has five.

Urkullu called for the creation of a 'new model' for the Spanish state based on the 'free accession of its nations', a reference to the Basque country and Catalonia which already enjoy considerable autonomy but want more.

The proposed 'pact' is similar to a 'road map' for a new relationship for the Basque region with the rest of Spain that was unveiled last year by Basque regional prime minister Juan Jose Ibarretxe who also belongs to the PNV.

The 'road map' includes a call for two referendums from October 2008 on the Basque region's future. It has already been rejected by Zapatero for being 'illegal'.

The PNV captured 34.2 percent of the vote in the Basque region in the last general election in 2004, giving it seven seats in the national parliament.