WASHINGTON • Former US president Barack Obama has accused his successor Donald Trump of trying to "actively kneecap the Postal Service" in order to hurt vote-by-mail in November.

In an interview with his former adviser David Plouffe, the former president pointed to Mr Trump's recent remarks linking his opposition to US$25 billion (S$34 billion) in emergency funding for the US Postal Service to his fears about mail-in ballots.

"What we've never seen before is a president say, 'I'm going to try to actively kneecap the Postal Service to encourage voting, and I will be explicit about the reason I'm doing it.' That's sort of unheard of, right?" Mr Obama told Mr Plouffe on Cadence13's Campaign HQ podcast.

Mr Obama, who has rarely spoken out about Mr Trump's actions in office, urged voters and elected officials to take steps to "protect the integrity" of the Nov 3 election.

The vast majority of states in the US have decided to allow mail-in voting in a bid to curb the spread of Covid-19.

But Mr Trump has repeatedly made unfounded claims that mail-in voting is rife with fraud and hurts Republican candidates.

Last Thursday, he said that by his not approving a financial lifeline sought by Democrats, it meant that "you can't have universal mail-in voting because they're not equipped to have it".

Democrats and voting rights advocates have criticised Mr Trump for deliberately stoking these unfounded concerns as a way to cast doubt about the outcome of the election.

They have also clashed with the US Postal Service under new postmaster-general Louise DeJoy, a major donor to Mr Trump's campaigns, for making mail-in voting difficult.

The Postal Service warned that it may not be able to meet individual states' deadlines for delivering last-minute mail-in ballots.

In letters sent last month to all 50 states and Washington DC, Postal Service general counsel Thomas Marshall told most of them that "certain deadlines for requesting and casting mail-in ballots are incongruous with the Postal Service's delivery standards".

He urged those with tight schedules to require that residents request ballots at least 15 days before an election - rather than the shorter periods currently allowed under the laws of many states.

"This mismatch creates a risk that ballots requested near the deadline under state law will not be returned by mail in time to be counted," Mr Marshall wrote.

Many states have long allowed voters to request a mail ballot close to the election, but the Postal Service suggested that the large volume of voting by mail at a time of widespread delivery delays meant that states would be better off building more time into their systems.

Mr Marshall said Nevada, New Mexico, Oregon and Rhode Island should not have any trouble, based on their laws, while he requested more information from Vermont and Washington.

The other 45 states, he told them in the letters, face the risk that the timetables set by their laws could leave some voters unable to get their ballots postmarked by Election Day or received by election boards in time to be counted.

The letters prompted some states to consider changes that would give voters more time to vote by mail or ensure their ballot would be counted.

"The Postal Service's announcement represents a significant change to the outlook for voting by mail in the general election," the state of Pennsylvania said in a legal petition to extend the postal voting deadline.

But prior to the letter, "the Postal Service had not indicated the likelihood of widespread, continuing, multiple-day mail-delivery delays presenting an overwhelming, statewide risk of disenfranchisement for significant numbers of voters utilising mail-in ballots".

But Colorado Secretary of State Jena Griswold said her state was prepared to handle the election.

She said ballots were sent out three weeks in advance, and voters could either put them in drop boxes or leave them at voting centres.

"Colorado's election model is well situated to handle both the delivery and return of mail ballots," she said in a statement.

"Starting eight days before an election we encourage voters to use one of these two options rather than the mail to ensure that their ballot is received by 7pm on Election Day." BLOOMBERG,

NYTIMES