Riikka Purra, chair of the Finns Party, said that immigration issues have yet to be resolved in negotiations on forming a new government.
The nationalist party leader spoke to reporters at the House of Estates in Helsinki as the third week of cabinet formation talks drew to a close on Friday.
Purra said she had reminded other negotiators that if there are no clear changes to the immigration policy, no government programme will be created involving her party.
She was asked whether immigration issues, which have been perceived as difficult for this planned government coalition, have been avoided by other parties.
"Maybe there is a kind of difficulty [with this issue]," Purra said, but went on to say that "without clear changes to Finnish [immigration] policy, a government will not be formed based on these parties."
According to Purra, there are problems in the talks regarding both work-related and humanitarian immigration.
According to the leading daily Helsingin Sanomat, the Finns Party is seeking changes such as limiting the right to seek asylum in Finland to internal European refugees and restricting the right to social security solely to Finnish citizens.
Development spending another bone of contention
According to Purra, no agreements have reached over funding for international development cooperation either. Her party has called for a sharp cut in such spending, which now corresponds to about 0.5 percent of Finland's GNP.
Meanwhile, two other potential coalition partners, the Swedish People's Party and the Christian Democrats, have demanded that development assistance be raised to 0.7 percent of GNP, in line with long-standing international guidelines.
Meanwhile, Christian Democrats chair Sari Essayah said that the government negotiations have progressed more smoothly than in 2011, the last time her party was involved. According to Essayah, negotiators are continually adding to the text of the government programme.
Essayah said that it was difficult to say whether the talks had already reached the halfway point.
Prime minister-apparent Petteri Orpo (NCP) estimated earlier this week that the parties were about halfway through the negotiation process. He said he aimed to have a new cabinet in office before the Midsummer holiday on 23 June.