North Korea will put US citizen Matthew Miller on trial next Sunday, state media said, shortly after he made a highly unusual televised plea for help from Washington along with two other detained Americans.
Miller, who is being held in North Korea along with Americans Kenneth Bae and Jeffrey Fowle, was arrested in April after Pyongyang said he ripped up his visa at immigration and demanded asylum.
North Korea said in June it would put Miller and Fowle on trial on unspecified charges related to "perpetrating hostile acts".
"The Supreme Court of the Democratic People's Republic of Korea decided to hold on September 14 a court trial on American Matthew Todd Miller, now in custody according to the indictment of a relevant institution," the official news agency KCNA said Sunday.
The statement offered no further details.
On September 1, the three men pleaded for their freedom in an interview with CNN.
As government minders looked on, they urged Washington to send an envoy to the isolated authoritarian state to negotiate their release.
"My situation is very urgent," Miller said.
"I think this interview is my final chance to push the American government into helping me," he added, wearing a dark turtleneck and often looking away from the interviewer.
US officials vowed after the footage was aired that they would "leave no stone unturned" in their efforts to free the trio, but declined to disclose details, saying they did not want to jeopardise any diplomacy.
State Department spokeswoman Jen Psaki would not discuss whether Washington was prepared to send a high-level envoy as it has in the past, when former president Bill Clinton and ex-governor Bill Richardson successfully won the release of detained Americans.
After the North's announcement Sunday, the State Department said there was no update to Psaki's earlier remarks.
Although religious freedom is enshrined in the North's constitution, it does not exist in practice and foreign missionaries -- viewed as seditious elements intent on fomenting unrest -- have been among those detained in the past.
Bae, a Korean-American described by the North as a militant Christian evangelist, was arrested in November 2012 and later sentenced to 15 years of hard labour on charges of seeking to topple the North Korean government.
Fowle entered the North on April 29 and was detained after reportedly leaving a Bible at a hotel.
Washington has no diplomatic ties with North Korea, and the Swedish embassy acts as a go-between in such consular cases. Swedish officials last visited Bae on August 11, and saw Fowle and Miller in late June.
The trial date for Miller has been set as the North launches a diplomatic offensive by sending senior diplomats on rare trips to Europe -- and, possibly, to the US.
Kang Sok-Ju, secretary of the central committee of the ruling Workers' Party, arrived Saturday for a European tour including Germany and Italy.
Foreign Minister Ri Su-Yong reportedly plans to visit New York to attend the UN General Assembly later this month, in the first visit to the US by anyone in the role of North Korea's top diplomat in 15 years.
As part of the renewed diplomatic campaign, Pyongyang will use the detainees as a bargaining chip to lead Washington to the negotiating table, said Kim Yong-Hyun, professor of North Korean Studies in Dongguk University.
"The North is hoping that the US will send a senior-level envoy, and hoping in this process to improve ties with Washington and make progress in nuclear negotiations," Kim said.
On his arrival in Berlin, Kang repeated calls for Washington to resume the long-stalled, six-nation nuclear negotiations.
"The US will put forward conditions (to restart the talks)... I'd say let's do it unconditionally," the South's Yonhap news agency quoted him as saying.
The aid-for-denuclearisation talks involving both Koreas, China, the US, Russia and Japan have been at a standstill since 2009. Seoul and Washington want Pyongyang to first show sincerity about abandoning its nuclear weapons programme before talks can resume.