Mateusz Morawiecki made the declaration after an informal meeting with a group of European Union leaders in Zagreb on Thursday, public broadcaster Polish Radio's IAR news agency reported.
The outgoing Polish prime minister, who has been offered a chance to form a new Cabinet, told a media briefing in the Croatian capital that "the process of forming the new government is under way."
"I will unveil the lineup of the new Cabinet in seven to eight days," he added.
Morawiecki also said that "it will be up to parliament to decide" whether the new Cabinet would be formed.
Polish President Andrzej Duda on Monday named Morawiecki as prime minister-designate, tasking him with forming a new Cabinet.
The constitutional deadline for the mission is 14 days, which means Morawiecki has to unveil the new government by November 27.
Poles elected a new set of 460 MPs and 100 senators when they went to the ballot box last month.
Morawiecki's ruling conservatives won Poland's October 15 election, but lost their parliamentary majority and look unlikely to stay in power for a third consecutive term.
A bloc of pro-EU opposition parties on Monday secured a resounding victory in Poland's new parliament during its first key vote to elect a house Speaker.
On November 10,Poland's pro-European opposition groups signed an agreement to form a coalition government, pledging to restore the rule of law, promote green energy and relax abortion rules, among other policies.
(pm/gs)
Source: IAR, PAP