NEW YORK, United States (AP) — A New York prosecutor has obtained copies of Donald Trump's tax records after the Supreme Court this week rejected the president's last-ditch effort to prevent them from being handed over.

The Manhattan district attorney's office enforced a subpoena on Trump's accounting firm within hours of the Supreme Court's ruling on Monday and now has the documents in hand, a spokesperson for the office, Danny Frost, said yesterday.

District Attorney Cyrus R Vance Jr had been fighting for a year and a half for access to Trump's tax records for a criminal grand jury investigation into his business dealings. The documents are protected by grand jury secrecy rules and are not expected to be made public.

Vance, a Democrat, is conducting a wide-ranging investigation that includes an examination of whether Trump or his businesses lied about the value of assets to gain favourable loan terms and tax benefits. The district attorney is also scrutinising hush-money payments paid to women on Trump's behalf.

Vance's office issued a subpoena to Trump's accounting firm, Mazars USA, in August 2019 seeking eight years of his tax returns and related documents.

Trump's lawyers immediately went to court to block its enforcement, first arguing that he was immune from being investigated while president.

When the Supreme Court rejected that argument 7-2 last July, Trump's lawyers returned to a lower court and argued the subpoena was issued in bad faith, overly broad, might have been politically motivated and amounted to harassment. An appellate court rejected that argument and the Supreme Court on Monday declined to intervene.

In a three-word statement after the Supreme Court ruled on Monday, Vance said only: “The work continues.”

Trump has called Vance's investigation “a fishing expedition” and “a continuation of the witch hunt — the greatest witch hunt in history”.

Vance is leading the investigation along with his general counsel, Carey Dunne, who made arguments on behalf of the office at various appellate court hearings. Vance recently hired former mafia prosecutor Mark Pomerantz as a special assistant district attorney to assist in the probe.

Vance, whose term expires at the end of the year, hasn't announced if he will seek reelection, leaving questions about who will lead any Trump-related prosecutions in the future.

Vance's subpoena sought from Mazars USA not only the final versions of Trump's tax returns, but also draft versions of those returns and “any and all statements of financial condition, annual statements, periodic financial reports, and independent auditors' reports” held by the company.

Mazars did not object to the subpoena and, in a statement at the time, said it would “respect the legal process and fully comply with its legal obligations”.

The Mazars subpoena also sought engagement agreements that define the accountants' role in creating the tax returns and financial statements; source documents providing the accountants with raw financial data; and work papers and communications between the firm and Trump representatives.

Those would include communications showing how the raw data was analysed and treated in the preparation of the records.