In its fight for LaSalle Bank, Bank of America [ticker: BAC] said in an appeal filing that it was “shocking” that the Dutch court would disregard fundamental European Union law.

The Charlotte, N.C.-based bank has accused a Dutch court of unlawful action by blocking its $21 billion purchase of Dutch banking giant ABN Amro’s U.S. unit.

In support of calls from investors, last month a Dutch commercial court froze the deal between Bank of America and LaSalle Bank in order to allow for a shareholder vote.

The Dutch Supreme Court is hearing appeals by both ABN and Bank of America over the frozen deal and will rule later this month or in early July on whether the sale can take place.