SEOUL: The massive earthquake that devastated northeastern Japan has shifted the country more than two metres away from the neighbouring Korean peninsula, scientists said on Thursday.

The Korea Astronomy and Space Science Institute (KASSI) said the Korean peninsula moved east up to five centimetres (two inches) while Japan shifted some 2.4 metres (7.92 feet) east.

Consequently, the distance between the countries increased by more than two metres, the institute said.

The disputed Dokdo islands, also claimed by Japan where they are known as Takeshima, relocated furthest, moving five centimetres east, as the islands in the Sea of Japan (East Sea) are relatively closer to the epicentre.

The southwestern port of Mokpo drifted 1.21 centimetres.

"We are closely monitoring to see whether the shift was temporary or perpetual," a KASSI spokeswoman told AFP.

"But don't worry. You will never feel the change anyway," she said.According to NASA, the 9.0 magnitude earthquake also shortened Earth's day by just over one millionth of a second and shifted the Earth's axis by about 6.5 inches.