NEW YORK >> President Donald Trump asked a federal judge today to block an effort by New York prosecutors to obtain his tax returns, opening a new legal front in the president’s efforts to prevent his financial information from becoming public.

Trump’s attorneys filed a lawsuit against the Manhattan district attorney, Cyrus R. Vance Jr., who recently subpoenaed the president’s accounting firm for eight years of his state and federal returns. They said the subpoena was unconstitutional and a “bad faith effort to harass the President by obtaining and exposing his confidential financial information.”

The lawsuit, filed in Manhattan federal court, asks U.S. District Judge Victor Marrero to declare the subpoena invalid and unenforceable. It says the U.S. Constitution “prohibits states from subjecting the president to criminal process while he is in office.”

Trump lawyer Jay Sekulow said the lawsuit is intended “to address the significant constitutional issues at stake in this case.”

A spokesman for Vance said the district attorney had received the lawsuit “and will respond as appropriate in court.” Trump’s accounting firm declined to comment.

The lawsuit marks Trump’s latest attempt to prevent his tax returns from becoming public and comes as his campaign is fighting a separate effort in California. A new law in the Democratic-led state says presidential candidates must release five years of tax returns to appear on the state’s March 2020 primary ballot. Trump’s campaign and the Republican National Committee have sued, and a hearing is set today in federal court in Sacramento.

Meanwhile, Democratic-led congressional committees are trying to obtain his tax returns and other records that could provide a window into his finances. Trump and three of his children filed a lawsuit in April seeking to block two House committees from getting records that his longtime lender, Deutsche Bank, has said includes tax returns. And in July, the president sued to block the application of a new state law in New York that could allow a House committee to obtain his state tax returns.

Vance also has subpoenaed the Trump Organization for records related to payments that former Trump lawyer Michael Cohen helped arrange to porn actress Stormy Daniels, who claimed she had an affair with Trump. The Democratic district attorney is also pursuing a mortgage fraud case against former Trump campaign chairman Paul Manafort.

Vance’s inquiry appears to be covering some of the same ground as federal prosecutors, who spent months probing payments made during the 2016 presidential campaign to two women who said they had affairs with Trump: Daniels and model Karen McDougal.

Cohen made one of the payments himself and arranged for American Media Inc., the parent company of the National Enquirer, to make the other. He pleaded guilty last year to campaign finance violations, tax evasion and other crimes and is serving a three-year sentence in federal prison.

Trump has denied any sexual relationship with either woman and said any payments were personal matters, not campaign expenses.