Maj. Gen. Gunnar Lange said he had handed a letter to President Boris Trajkovski informing him of the completion of the first phase of the weapon's collection program.
According to a peace plan, the rebel handover of weapons is to be followed by step-by-step political reforms that would give Macedonia's ethnic Albanian minority greater rights.
Parliament is expected to begin debating the reforms favoring the ethnic Albanian minority on Friday after a third of the weapons have been handed in. Voting on the legislation will only occur when the goal of 3,300 weapons has been collected.
Lange told reporters he informed the president that more than one third of the weapons that the National Liberation Army are voluntarily going to hand over have been collected. Â"And I really hope that this will contribute to the parliament process,Â" he said.
Meanwhile, an explosion rocked an ethnic Albanian commercial district of Skopje early Thursday, the fourth to hit the capital in as many days, causing no injuries but increasing tensions.
Residents saw anti-terror squads investigating the site of the explosion that destroyed an Albanian-owned restaurant. Three other explosions, none of which caused any injuries, have occurred here over the past few days.
Elsewhere Thursday, Macedonian villagers from Matejce, 14 miles north of Skopje, blocked another nearby border crossing to protest NATO's mission.
During NATO's 30-day Operation Essential Harvest, thousands of troops, including Americans, are collecting weapons from ethnic Albanian rebels, who staged an insurgency for six months in a struggle to win more rights for their people.
On Wednesday, NATO's Secretary-General Lord Robertson urged Macedonia's parliament to pass legislation envisioned in a peace deal, saying the alternative could be another Balkan war.
The legislation is meant to give the ethnic Albanian minority, who makes up a third of Macedonia's two million population, more rights.
Â"This country has the chance to show that it is possible to deal with an internal conflict before the blood starts to pour down the streets,Â" Robertson said after several hours of meetings with Macedonian officials.
Â"Members of parliament will hold the future of this country in their hands when they vote in the next few weeks,Â" Robertson said. Â"I don't think that there is much of an alternative to what is being put forward now.Â"
But with the disagreement over numbers continuing, parliamentary hard-liners could stall the debate.
Macedonian government officials have criticized the mission, saying the numbers of arms the alliance has said it expects to collect are far below the true size of the rebel arsenal. The alliance has said it expects 3,300 weapons, while the government insists the true size of the rebel arsenal is closer to 60,00.
In a newspaper report, Robertson said the monthlong arms-collecting mission may be extended by a few days, but the alliance will not play a long-term peacekeeping role. Â"Those challenges are political and must be met politically,Â" he wrote in the Financial Times of London.
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