Donald Trump’s trial on charges that he retained classified documents at his Mar-a-Lago club and obstructed justice is running about four months behind schedule after the federal judge presiding in the case in Florida declined to set a crucial filing deadline until at least next March.

The US district judge Aileen Cannon put off setting a deadline for Trump to submit a notice about what classified information he intends to use at trial – currently set for May – until after a hearing next year that almost certainly precludes the pre-trial process from finishing in time.

Trump was indicted this summer with violating the Espionage Act when he illegally retained classified documents after he left office and conspiring to obstruct the government’s efforts to retrieve them from his Mar-a-Lago club, including defying a grand jury subpoena.