Belgian firefighters were pushing to encircle and contain the country's largest wildfire in a century.

Rain and cooler temperatures provided some natural relief against the blaze on Tuesday but also teamed up with winds to hamper air support and waterbombing operations.

The fire expanded to cover an area of around 3,000 hectares — about half the size of Manhattan in New York — by Monday.

The High Fens, or Hautes Fagnes, nature reserve is a vast expanse of boggy peatlands, pine forests and hiking trails, with parts of it difficult to access with large machinery, except from above. 

What's the latest on the firefighting efforts? 

"We are trying to definitively encircle the fire today," regional government spokesman Niolas Yernaux told the AFP news agency on Tuesday. 

Firefighters worked through the night to try to make a crucial link-up between the eastern and northern fronts, despite difficult access conditions in the hilly and wooded area. 

"We're talking about one or two kilometers, and we're on the verge of achieving it," Yernaux said. 

He said that the fire was "under control and contained" in areas where firefighters could operate. 

However, Yernaux said the hard-to-reach front stretching towards the German border and the town of Monschau remained a concern; much of this area is only really accessible from above. The wind and rain could delay such aerial operations, potentially until Tuesday evening, he warned.

How far from the border is the fire, what's the situation in Monschau? 

Residents of Monschau have already been told to leave their homes because of the smoke hazard, with the fire roughly 2.3 kilometers (roughly 1.5 miles) from the border. Yernaux said that "strong winds" were blowing towards the east and the German frontier. 

"At the moment it's manageable," Monschau fire service spokesman Tobias Schnell told the dpa news agency. Should the winds pick up further, he said that could fan the flames in the town's direction. 

He said that water tanks and other equipment had already been placed in its potential path in case it is needed. He said around 170 people were working on a three-shift rotation around the clock, and that authorities were working on the assumption the operation would last several more days at least. 

Smoke has spread dozens of kilometers to the east, with major cities like Cologne and Wuppertal both warning residents of the risk of poor air quality and smoke. 

"At present the smell of the fire can be perceived throughout the city," Wuppertal's fire department warned, recommending that people close doors and windows. "A health risk cannot be ruled out." 

Locals start to return, but still urged to limit movements

Villagers in places like Sourbrodt, which was evacuated at the peak of the fire over the weekend, started returning to their homes as the threat subsided on Monday evening. 

Nevertheless, the local Waimes municipality asked residents to exercise continued caution. 

"Residents are asked to limit travel within this area to what is strictly necessary and to act with particular vigilance and responsibility," it said. "Despite the return of evacuated residents, operations carried out by the various emergency, security and response services remain a priority and must be able to proceed under the best possible conditions." 

Two villages in the Bütgenbach municipality, meanwhile, remain cleared, with conditions not yet safe there. 

Wallonia's Agriculture Ministry also said on Tuesday that it would review compensation for farmers who volunteered to help with the firefighting efforts. 

This is was "under review — regarding both the substance and the procedure, as well as the legal feasiblity of doing so," Agriculture Minister Anne-Catherine Dalcq's office said on Tuesday. 

This followed an appeal from the presdient of the Royal Federation of Belgian Firefighters, who demanded reciprocal aid after the farmers' help battling the blaze. 

"Who will cover the cost of the equipment damaged during this operation? Without them, the situation would be far worse," Marc Gilbert had said in an interview with the Belga news agency. 

The vast fire gathered pace just after another a few kilometers east across the German border in the Hürtgenwald forest was contained late last week.

Edited by:  Saim Dušan Inayatullah

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