North Korea on Saturday accused South Korea and the United States of heightening tensions on the Korean Peninsula with aerial reconnaissance activities.

In a commentary carried by the Korean Central News Agency, the North said that Seoul and Washington have been stepping up their "spying activities" this month, calling such a move a "stern provocation" against the country.

The North claimed the countries attempted to secure information on the North's inner regions by conducting surveillance activities with the US RC-135 Combat Sent and RC-135W Rivet Joint and South Korea's advanced high-altitude unmanned aircraft Global Hawk and E-737 Peace Eye early warning aircraft.

The North said it is closely monitoring such military activities and threatened that it is ready to destroy its enemies anytime.

North Korea has ratcheted up tensions on the Korean Peninsula with weapons tests this year, including launches of cruise missiles from sea and land, as well as artillery firings into waters near the western inter-Korean sea border.