Bangkok authorities insisted on Tuesday they could not ease the flooding crisis for everyone in the city, as anger and misery grew in inundated areas over the lack of assistance from officials.

Although inner areas of the capital have remained dry, the situation is critical in several outlying districts, where residents have protested that their homes are being sacrificed to save central parts of the city.

But Bangkok authorities justified efforts to spare the glitzy downtown area as much as possible by diverting the brunt of the water to other neighbourhoods.

"Bangkok is the heart, you can cut your hand but you have to save your heart, because if your heart fails, everything fails," Jate Sopitpongstorn, a spokesman for the Bangkok Metropolitan Administration (BMA), told AFP.

Thailand's worst flooding in decades, triggered by unusually heavy monsoon rains that began three months ago, have claimed more than 380 lives and affected the homes and livelihoods of millions across the kingdom.

Inflation rose in October as flood damage to farmland forced up food prices, according to government data released on Tuesday.

Prime Minister Yingluck Shinawatra and Bangkok officials have clashed over how much water should be let through certain sluice gates to the north of the city centre to ease the pressure on inundated communities.

On Monday, Yingluck caved in to protesters and ordered a gate in the northeastern district of Khlong Sam Wa to be raised to one metre (three feet) to allow more water through and relieve those in the immediate vicinity.

But Bangkok governor Sukhumbhand Paribatra on Tuesday warned the move could put other areas of the city, including industrial estates, at risk of flooding if other gates further north were not closed.

He said he had to consider the needs of all of the megacity's economic and political heartland.

"I love the people, as do other elected politicians, but sometimes I have to be tough with the demands of the minority for the sake of the majority," Sukhumbhand said in a televised press briefing.

"I cannot yield to every demand," he said, adding city authorities and the government should try "to find a common position".

Central Bangkok has largely been spared from major inundation after barriers along Bangkok's swollen Chao Phraya River prevented a major overflow during a spring high tide over the weekend.

But in districts such as western Bang Phlat, just five kilometres (three miles) from downtown Bangkok, homes were badly damaged and streets turned into deep canals of filthy water, with no official help in sight.

"I want the government to come and take care of us. We have asked for help but nobody comes. We asked for boats, food, medicines, but nothing," said Pailin Sontana, 58, as he waded waist-deep through the brown liquid.

Yupin Songsuk, a 38-year-old housekeeper at a hotel, said the situation showed no signs of improving, with more water on the way.

"We can still eat and drink the things we stocked, but what about later on, if nobody comes to help us?" she told AFP.

BMA spokesman Jate admitted they were unable to help everyone who refused to move to a shelter. "We have limited numbers of army vehicles and boats and we cannot go into every street and hand out food and water three times a day."

And an official from the government's Flood Relief Operations Centre (FROC) said parts of western Bangkok could be inundated for another month because of ineffective drainage systems.

Further east, Bangkok's main international air hub Suvarnabhumi is operating as normal but Don Mueang airport, the city's second-largest which lies to the north, has been shut for a week.

"I have assigned the air force chief to pump out water from Don Mueang airport's taxiways and runways before Friday," Defence Minister General Yuthasak Sasiprapa told reporters.