The Indian diplomat at the centre of a standoff between the United States and New Delhi has asked a court to postpone her first hearing while a settlement is pursued.

The lawyer for Devyani Khobragade sent a letter to Judge Sarah Netburn, of the US District Court for the southern district of New York, requesting a delay beyond next Monday.

Daniel Arshack’s letter alleged that federal prosecutors sought to “rapidly” proceed to indictment by next Monday.

Khobragade, 39, was charged on December 12 with supplying false documents to support a visa application for her Indian housekeeper.

She was also charged with paying the employee less than agreed in a contract.

Khobragade, who is out on bail, is India’s deputy consul general in New York.

Her arrest triggered retaliatory measures by the Indian government against US diplomats.

· US marshals strip-searched Indian diplomat

New Delhi has demanded the US State Department or President Barack Obama intervene in the case.

But US officials said they have explained that they are not allowed to do so in the US justice system.

The preliminary hearing is scheduled for Monday.

A defendant can request a delay, thus waiving the right to a speedy trial.

Arshack wrote that the delay would help to “avoid further polarisation” and “permit the efforts which are ongoing to resolve this matter”.

Khobragade was freed on a $US250,000 ($A281,000) bond, after being strip-searched and held in a cell, leading to strong protests by India and a major diplomatic row.