Mitsubishi UFJ Financial, Japan's largest bank, is interested in buying the trust business of Morgan Stanley, media reports reveal.

The trust arm, which offers fiduciary and administrative services to high net worth clients, operates under Morgan Stanley's wealth management division.

Both firms have yet to officially confirm that talks between them are taking place, but unnamed sources have reportedly told Bloomberg that a deal is in the works and is only pending US regulatory approval. Morgan Stanley has not responded to inquiries from WealthBriefingAsia as of this writing.

Should the transaction push through, the Mitsubishi UFJ expands its reach to include the $4 billion in client assets under Morgan Stanley's trust business.

Financial terms are still unknown.