The backlog this year has grown at a record pace, said the Transactional Records Access Clearinghouse at Syracuse University, which tracks immigration court data, on Wednesday.
The figure has nearly doubled since President Trump took office in January 2017, when about 542,000 cases were pending, Efe news reported
The growing backlog was due in part to the surge of Central American families crossing the US-Mexico border this year, with more people crossing illegally in May than during any other month in a decade.
The Trump administration's crackdown on illegal immigration has also contributed, experts say.
The administration has pushed recent border-crossers to the front of the queue, in an effort to deport them faster and send a message that unauthorized immigrants seeking asylum could no longer stay in the country for years as their cases wend their way through the courts.
That has had the effect of delaying court dates for asylum seekers who arrived in the country earlier.
The administration's actions have had the effect of allowing most people who already have asylum cases pending to stay longer - though TRAC data suggest most of these immigrants will ultimately not qualify for asylum.
Asylum seekers are currently issued work permits while they wait, though the administration has moved to do away with the requirement to issue these work permits.
The Trump administration has argued that the extensions and work permits provide a back door for immigrants to stay in the country and that the wait times have made crossing the border only more attractive for prospective migrants.
The Justice Department, which oversees the immigration courts, has pressed individual judges to move through cases faster, giving judges a one-year deadline to decide each case and setting a 700-case annual quota.
Only about a third of judges are on track to meet that goal, according to Ashley Tabaddor, president of the National Association of Immigration Judges, a labour union.
The Justice Department has also hired more judges to speed up processing. About 400 judges are working today, according to the union, compared with about 280 at the end of the Obama administration.
Last week the government also set up temporary tent courts that are closed to the public, to hear the cases of asylum seekers the Trump administration has required to remain in Mexico while awaiting court dates.
Meantime, the Trump administration has taken steps to limit applications for asylum, which it argues will allow courts to concentrate on existing cases.
The Supreme Court last week allowed the administration to begin enforcing a policy preventing nearly all immigrants from Latin America, except those of Mexican origin, to qualify for asylum.
( With inputs from IANS )