North Korea now has 1,000 missiles of various types, South Korea's defence minister said Wednesday, a 25-percent increase on the number estimated two years ago.

Minister Kim Tae-Young also reminded a Seoul forum that the communist state is pushing ahead with a highly enriched uranium programme, a second way to make atomic weapons in addition to its plutonium enrichment.

The 1,000 missiles include Scuds, Rodongs and IRBMs (intermediate-range ballistic missiles), a ministry spokeswoman told AFP. Two years ago, the ministry estimated the total at around 800.

Many of the missiles are deployed near the inter-Korean border and targeted at Seoul or other locations in the South, officials have said.

Yonhap news agency said last week the North has set up a new military division to operate IRBMs with a range of more than 3,000 kilometres (1,860 miles), capable of hitting US bases in Japan and Guam.

It is also known to have test-launched three intercontinental Taepodong missiles, which in theory could reach Alaska.

Kim, reiterating earlier estimates, said the North has produced 30-40 kilograms (66-88 pounds) of weapons-grade plutonium from its plutonium programme. Experts say this is enough to build six or seven bombs.

It is not known whether the North yet has the technical capability to create a nuclear warhead.

Pyongyang conducted two underground nuclear tests in October 2006 and May 2009. Recanting its earlier denials, last September it also announced it is running an experimental highly enriched uranium programme.

The North is under diplomatic pressure to return to six-nation nuclear disarmament talks which it quit last April.

As conditions for resuming dialogue, it insists on a lifting of UN sanctions and a US commitment to start talks about a permanent peace treaty.