Madrid - The first pro-Spanish government of Spain's Basque region is to step up the fight against the militant separatist group ETA, regional prime minister-designate Patxi Lopez vowed Wednesday.

Lopez, a Socialist, is to be sworn in on May 5 as the region's first prime minister clearly defending its unity with Spain since it was granted a broad self-government three decades ago.

Lopez will succeed moderate Basque nationalist Juan Jose Ibarretxe, whose Basque Nationalist Party (PNV) favours weaker ties to Spain.

Lopez and Basque conservative leader Antonio Basagoiti confirmed that Lopez will head a minority government with the backing of the conservative People's Party (PP).

The new government would "pursue and detain terrorists" and "leave no space of impunity" for organizations defending the violence of ETA, Lopez vowed.

ETA has pledged to respond with a new wave of violence.

Lopez' comments followed the arrests of nine ETA suspects in France and Spain over the weekend.

They included ETA's military leader Jurdan Martitegi, who was making preparations for a car bombing to coincide with the swearing in of Lopez, according to the Interior Ministry.

ETA, which has killed more than 820 people since 1968, is regarded as a terrorist organization by the European Union and the United States. (dpa)