Official rules say the government should keep gifts worth more than £140 unless ministers pay the value over that limit.
Keir Starmer bought a pair of personalised silver cufflinks which were given by Donald Trump and his wife, Melania, according to the latest transparency records.
The cufflinks, which were worth more than £140, were an official gift from the Trumps during the US president's historic second state visit last September.
They were the second Trump gift Starmer has chosen to buy, after paying for a personalised necklace last year.
Official rules say that the government should keep ministerial gifts worth more than £140 unless the minister in question decides to pay the value over that limit.
Downing Street would not reveal the exact value of the cufflinks, which are understood to have been purchased as a gift for the prime minister's son.
Last year's visit was a carefully stage-managed affair during which the president received the largest military ceremonial welcome for a state visit in living memory before being hosted by the king at Windsor castle for a lavish dinner.
During the visit Starmer gave the president a ministerial red box embossed with the presidential seal and title, and the first lady a silk scarf designed by Ukrainian children.
In return he received a personalised silver necklace, personalised silver cufflinks and a personalised golf club. His wife, Victoria, received a pair of women's cowboy boots.
The Cabinet Office said last year Starmer had chosen to buy the necklace, but that the cufflinks, golf club and cowboy boots had all been retained by the department. The prime minister only recently decided to buy the cufflinks, according to officials.
The records show he received a number of other gifts in September worth more than £140.
They included a wooden carving from Mahmoud Abbas, the president of the Palestinian National Authority; a personalised rugby shirt, leather boots and beer from the Australian prime minister, Anthony Albanese; and a display model of an AI supercomputer from the technology company NVidia. All were retained by the department rather than being bought by Starmer.
Ministerial gifts can occasionally cause diplomatic controversy, such as when Barack Obama gave Gordon Brown a DVD box set of 25 classic American films during the former prime minister's visit to Washington in 2009. Brown in contrast had given the then president an ornamental pen holder crafted from the timbers of the anti-slavery ship HMS Gannet.
Gifts from Trump have also previously caused upset, albeit in his private life.
The actor Charlie Sheen told the Graham Norton show in 2016 that Trump had given him fake diamond and platinum cufflinks embossed with "Trump" as a wedding present.