MUMBAI: Indian tax officials on Wednesday threatened to cut their workloads in protest over working conditions, a move that could dent New Delhi's tax collection just as the government scrambles to fill coffers before the fiscal year ends on March 31.Prime Minister Narendra Modi 's government is pushing to shore up revenue as India's once-booming economy grows at roughly 11-year lows.Corporate and income tax collection for the current year is likely to fall for the first time in at least two decades, several senior tax officials said.In a statement on Wednesday, two unions representing some 97% of tax officials said they were beginning action for improved working conditions, including the resolution of " pay anomalies " and set contracts for casual workers.If demands are not met, the unions are planning to stop submitting certain reports and halt search and seizure operations on March 12, before putting an end to overtime work on March 15."We go beyond our limits and work for the government. There should some recognition at least for that," said Dipak Gupta, general secretary at the Income Tax Gazetted Officers' Association's Mumbai unit.In a Feb. 26 letter to the Central Board of Direct Taxes that was seen by Reuters, the unions said there was "undue pressure" on officials to collect taxes and that staff were suffering from unclear promotion rules and career stagnation.In the letter, the unions said they believed the government would intervene by next Tuesday, in which case they would call off planned protests.The CBDT and the Finance Ministry did not immediately respond to a request for comment on the planned action.Separately, a letter from the CBDT seen by Reuters on Wednesday said it was imperative for officials to make a new amnesty scheme, called Vivad se Vishwas, a success."The performance of officers ... shall be an important factor in determining their future postings," the letter read.Ravi Shankar, the secretary general of the Income Tax Gazetted Officers' Association, said tax officials had promised the government to leave "no stone unturned" to make the scheme work, but stressed that New Delhi should also "redress our long pending demands."