The Polish Prime Minister, Mateusz Morawiecki, has made a statement in regard to assisting Finland and Sweden if Russia attacks them prior to their admission into NATO.
Source #2 National Post
Source #3 US News
"I consider the accession of Sweden and Finland to NATO as an important signal of strengthening security in Europe... ...I want to make it clear that in the event of an attack on Sweden or Finland during their accession, Poland will come to their aid."
-Mateusz Morawiecki, Poland Prime Minister
Source #1 Reuters
Source #2 National Post
Source #3 US News