Any remote possibility of returning to the Whigs was scuttled by the Lichfield House Compact by which the Irish Repealers, Whigs and Radicals agreed to vote out Peel's government.
The possibility of returning to the Whig party was eliminated by the Lichfield House Compact, a pact between the Irish Repealers, Whigs, and Radicals that resulted in their decision to oust Peel's government.