Afghan President Najibullah told foreign diplomats Saturday that the United States and Pakistan risked provoking a regional war.

"Violations of the Geneva accords by Pakistan and the U.S.A. pose a serious threat to the political independence, territorial integrity and national sovereignty of our country as a result of which one cannot consider impossible the danger of a regional war," Najibullah said in a speech marking the first anniversary of the accords.The agreements, under which the Soviet Union agreed to pull its troops out of Afghanistan, guarantee non-interference in Kabul's affairs.

Najibullah accused Pakistan of planning to annex Afghanistan and giving large quantities of arms to the mujahideen guerrillas fighting his pro-Soviet government.

"After the completion of the withdrawal of Soviet troops, the military intelligence of Pakistan with the direct and wide support of the armed forces of that country . . . have resorted to armed and open aggression against our country and disclosed their evil designs of merging our country with Pakistan," Najibullah said.

Arms and funds for the mujahideen flow through Pakistan but it has repeatedly denied giving the reb-els military help in their 10-year-old war to take power in Kabul.

The last Soviet troops pulled out Feb. 15, leaving the Afghan army to take on a loose mujahideen alliance single-handed.