Japanese defence minister Minoru Kihara said on Thursday he had discussed with US defence secretary Lloyd Austin expediting Japan’s acquisition of Tomahawk cruise missiles by 2025, although recent upheaval in the US Congress was a "bit of a concern".

Kihara, on his first visit to Washington after being appointed by Prime Minister Fumio Kishida in a cabinet reshuffle last month, met with Austin at the Pentagon on Wednesday.

"The original plan, before I assumed this position of defence minister, was to acquire Tomahawk missiles by JFY 2026 and 2027," he told Washington's Hudson Institute think-tank, referring to Japan's fiscal year that runs from April to March.

"But we decided to expedite the process and start acquiring them from JFY 2025, which is one year ahead of the original schedule," he said, adding that he had discussed the issue with Austin in their meeting.

Kihara said he expected the US government to take necessary steps for congressional approval of the acquisition, although he added that the recent situation in the US Congress was "a bit of a worry", referring to budget-related upheaval in the US legislature that has threatened a government shutdown.

Kishida said in February Japan was considering buying 400 of the Tomahawk missiles, which are made by Raytheon Technologies Corp. Tokyo has earmarked $1.6 billion for the purchase, part of its biggest military build-up since World War Two.

While a US government shutdown would slow the contracting and bureaucratic approval process for foreign military sales, a Tomahawk sale to Japan, a major US ally with a long history of both co-production and purchases of advanced US weapons, is unlikely to run into any congressional oversight issues.

Kihara said Japan was developing its own stand-off missiles for counter-strike capabilities, but this would take time, so it had decided to acquire Tomahawks in the meantime. (Reuters)