U.S. President Donald Trump on Monday congratulated Prime Minister Shinzo Abe on his ruling camp's big victory in the general election the previous day.

During their 30-minute telephone talks, Trump told Abe it is important for a strong leader to gain firm public support, according to a senior Japanese government official.

In response, Abe said he had stressed in all his stump speeches the necessity of "placing as much pressure as possible on North Korea so it will change its policies under the unshakable Japan-U.S. alliance," in the face of the country's nuclear and missile provocations, the official said.

Abe's Liberal Democratic Party and its coalition partner Komeito party secured a two-thirds majority in Sunday's House of Representatives election.

Abe and Trump also agreed to deepen their discussions on how to address Pyongyang's threats during the latter's planned visit to Japan early next month, the official said.

The Japanese prime minister also thanked Trump for his willingness to meet with the kin of Japanese nationals abducted by North Korean agents decades ago.