The Washington Free Beacon on Tuesday reported that China had on April 12 again tested a new long-range missile called the DF-41.

It did not say where the test took place but noted it came ahead of a visit by U.S. Defense Secretary Ash Carter to the aircraft carrier USS Stennis in the South China Sea.

The Chinese Defence Ministry in a statement on its website in response to the report said that routine research tests on Chinese territory were normal.

"These tests are not aimed at any set country or target," it said.

The Washington Free Beacon said it did not know where the test happened, though the Defence Ministry said reports said it had happened in the vicinity of the South China Sea.

"Media reports about the test location are pure speculation," it said, without elaborating.

The ministry confirmed in December that China was testing the missile. The Washington Free Beacon said U.S. intelligence agencies had recently monitored a test of the DF-41, which can be mounted on a train.

Chinese President Xi Jinping is overseeing an ambitious military modernisation programme, including developing stealth fighters and building its own aircraft carriers.

That has rattled Beijing's neighbours, several of whom are engaged in territorial disputes with China, as well as Washington.

China says it has no hostile intent and that it needs a modern military to protect its legitimate security needs as the world's second-largest economy.