The subpoenas demanded their testimony in an investigation into the family’s business practices.

Attorney General Letitia James’ office said in a court filing it recently issued subpoenas seeking the Trumps’ testimony and documents as part of a years-long civil probe involving matters including “the valuation of properties owned or controlled” by Trump and his company.

Messages seeking comment was left with lawyers for the Trumps and the Trump Organisation.

The attorney general’s attempt to get testimony from the former president was reported in December but the court filing on Monday was the first public disclosure investigators were also seeking information from Ivanka Trump and Donald Trump Jr.

The Trumps are expected to file court papers seeking to quash the subpoenas, setting up a legal fight similar to one that played out last year after James’ office subpoenaed another Trump son.

Trump sued James last month, seeking to end the investigation after she requested that he sit for a January 7 deposition.

Trump’s lawsuit, filed in federal court, alleges that the probe has violated his constitutional rights in a “thinly-veiled effort to publicly malign Trump and his associates”.

Monday’s court filing was the attorney general office’s first public acknowledgement that it has previously subpoenaed Trump’s testimony.

James, a Democrat, has spent more than two years looking at whether the Trump Organization misled banks or tax officials about the value of assets – inflating them to gain favourable loan terms or minimising them to reap tax savings.

James’ investigators last year interviewed one of Trump’s sons, Trump Organization executive Eric Trump, as part of the probe.

James’ office went to court to enforce a subpoena on the younger Trump and a judge forced him to testify after his lawyers abruptly cancelled a previously scheduled deposition.

Although the civil investigation is separate from a criminal investigation being run by the Manhattan district attorney’s office, James’ office has been involved in both.

“As her investigation into financial dealing of the Trump Organization continues, Attorney General James is seeking interviews under oath of Donald Trump, Donald Trump Jr., and Ivanka Trump,” James’ office said in a statement on Monday.

“Despite numerous attempts to delay our investigation by the Trump Organization, we are confident that our questions will be answered and the truth will be uncovered because no one is above the law.”