Updated

The military commander of NATO's mission in Macedonia said Thursday that his force has collected more than one third of ethnic Albanian rebels' weapons.

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.

U.S. Maj. Barry Johnson, the NATO spokesman in Skopje, told The Associated Press that a total of 1,400 weapons have been collected so far. He gave no specifics on the type of weapons, but said that the overall operation is ahead of schedule.

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.

"I really hope that this will contribute to the parliament process," Lange said.

Parliament is expected to begin debating the political reforms on Friday now that one-third of the weapons have been handed in. However, enactment of the reforms will only occur when the goal of collecting 3,300 weapons has been reached.

The NATO mission began this week and is slated to end within a month. But NATO Secretary-General Lord Robertson on Wednesday suggested that his alliance was ready to play a future role in the country, and on Thursday, British Foreign Secretary Jack Straw acknowledged the weapons culling mission itself might extend its original 30-day limit.

"Nothing, particularly in the Balkans, is inevitable," Straw told BBC radio. "If you're asking me whether that NATO decision may change, it could change."

Macedonian officials have criticized the NATO mission, saying the total number of arms the alliance is to collect is far below the true size of the rebel arsenal. The government insists the rebels have closer to 60,000 weapons.

Ethnic Albanian rebels staged an insurgency for six months this year in a struggle to win more rights for their people, a third of Macedonia's 2 million population.

Despite the reported progress, tensions persisted.

An explosion rocked an ethnic Albanian commercial district of Skopje early Thursday, the fourth to hit the capital in as many days. No injuries were reported.

Residents saw anti-terror squads investigating the site of the pre-dawn explosion that destroyed an Albanian-owned restaurant.

Macedonian parliament speaker Stojan Andov condemned the explosion, warning the blasts represent a "threat that could complicate the peace process."

In other incidents, Macedonians blockaded the Blace crossing on the border with the NATO-run Serbian province of Kosovo, delaying the arrival of German soldiers who are part of NATO's mission here. Macedonian villagers from Matejce, 14 miles north of Skopje, also blocked a nearby border crossing to protest NATO's mission.

On Wednesday, Robertson urged Macedonia's parliament to pass the legislation envisioned in the peace deal, saying the alternative could be another Balkan war. But with the disagreement over arms numbers continuing, parliamentary hard-liners could stall the debate.

In talks with Robertson, Trajkovski insisted the criteria for the success of the mission include whether refugees will be allowed to return and whether the Macedonian government was able to regain control of territory now held by rebels.

Robertson stressed that such issues were more the concern of "other organizations which are a critical part of this peace process," and not of NATO alone.

However, Robertson left the option open for possible future international involvement in Macedonia, if asked for by the government.

"I don't think the international community could stand back if the people of Macedonia cry for help," he said.

In Vienna, Macedonian Foreign Minister Ilinka Mitreva on Thursday formally asked the Organization for Security and Cooperation in Europe to double the number of border monitors it has in the region.

The OSCE began monitoring the border with Macedonia in 1992 to help prevent violence in the former Yugoslavia from spilling over into Macedonia.

Mitreva also said Macedonia "desperately" needs the financial help of the international community because it is "on the verge of economic collapse."