Ugandan teachers went on strike for the second time this year on Monday after fruitless month-long talks with the government for a 100 percent pay rise, the latest in a string of protests in the east African country.

Teachers first went on strike in July, joining other Ugandans protesting over soaring living costs, before resuming talks with the government. The government said the latest strike was illegal and threatened to sack those participating.

An executive member of the Uganda National Teachers Union (UNATU), Steven Lugesi, told Reuters they had decided to resume their protest as schools reopen for a new term after the government insisted it could not meet the salary demands.

We agreed in July to suspend our strike to allow negotiations with government to proceed because they had signaled that they were willing to listen to us, Lugesi said.

Last week, they were categorically clear that they can't increase our salaries no matter what. And we also decided we won't step in class starting today until we get what we want, he said.

Teachers, estimated to number 160,000, are some of the lowest paid civil servants in Uganda. On average, a primary teacher earns 250,000 shillings per month while secondary school counterparts take home 450,000 shillings.

Although the government acknowledges teachers are underpaid, it says it does not have the money to fund a 100 percent rise and has promised to raise their salaries by 30 percent in the next financial year, which starts in July 2012.

We have communicated our position very clearly to them but they don't seem to understand and appreciate the challenges that government faces, Information Minister Karoro Okurut said.

So, any teacher who fails to turn up or turns up but doesn't teach without any reasonable cause will be deemed to have absconded from duty and will be sacked without further notice, the minister said.

President Yoweri Museveni has faced mounting public pressure over the rising cost of living which he says is caused by high international fuel prices and temporary food shortages.

Year-on-year headline inflation leapt to an 18-year high of 21.4 percent in August from 18.8 percent in July, fueled by a weak local currency and rising food prices.

Opposition-led demonstrations in April and May against sky-high prices of food and fuel prompted a government crackdown that killed nine people and injured hundreds.