BERLIN — Aldi is continuing to expand aggressively in the United States, but the retailer’s growth prospects in other countries may be being threatened by a family dispute, according to an interview that appeared recently in the German financial newspaper Handelsblatt.

Theo Albrecht Jr., in what is described as his first-ever interview, said that a legal dispute pitting him against the widow of his late brother and two of her daughters threatens the company’s ability to make decisions at a time when Aldi faces increased competition from Lidl and other retail rivals.

Aldi was founded by German brothers Karl and Theodor Albrecht. They established two companies — Aldi Nord (north) and Aldi Sud (south) — which divided the German market between them. Later each expanded internationally. Theo Albrecht Jr. is the heir to the Aldi Nord business, which operates Aldi stores in such countries as Belgium, Denmark, France, the Netherlands, Poland, Portugal and Spain as well in northern Germany. It also runs the Trader Joe’s chain in the United States.

Aldi’s U.S. business, which recently expanded into Southern California and has just introduced a full line of baby products under the Little Journey brand name, is part of Aldi Sud.

In the interview, Theo Albrecht Jr. cited the legal battle between himself and Babette, the widow of his late brother Berthold. Babette’s daughters have been named, via court action, to lead the board of the Jakobus Foundation, one of three foundations linked to Aldi Nord. Their positions allow them to block key company decisions, according to Albrecht, who is appealing the court action.

“If the old rule really remains in place, the children of Berthold, together with their lawyer, could lead this company around by the nose,” Albrecht told the newspaper.

The Handelsblatt article noted that the widow and her daughters dispute that view, and court documents show that they have not blocked any major company decisions. But Albrecht contends that decisions about modernizing stores in France and Denmark have not been made, and that stores in Germany, too, need to be updated.

“Standing still means stepping backwards,” Albrecht told Handelblatt. “This is about the future of the company.”