The possible closing of more than 400 post offices across the US in an effort to cut costs could further dent the struggling commercial property market as rising retail vacancies continue to weigh on prices.

The US postal service has said it is placing 413 of its 37,000 retail locations under review for “consolidation” as it faces a record loss of $6bn this year. The mail carrier has seen a dramatic drop in package volume because of cost-conscious Americans cutting back on sending in favour of cheap alternatives such as e-mail.