The Security Council,
Having considered the letter dated 1 May 1978 from the Secretary- General to the President of the Security Council,
Recalling its resolutions 425 (1978) and 426 (1978) of 19 March 1978,
1. Approves the increase in the strength of the United Nations Interim Force in Lebanon requested by the Secretary-General from 4,000 to approximately 6,000 troops;
2. Takes note of the withdrawal of Israeli forces that has taken place so far;
3. Calls upon Israel to complete its withdrawal from all Lebanese territory without any further delay;
4. Deplores the attacks on the United Nations Force that have occurred and demands full respect for the United Nations Force from all parties in Lebanon.