NEW YORK, Oct 29 (Reuters) - The U.S. Treasury Department is expected to reduce the size of its upcoming auctions when it announces its funding plan for the coming quarter on Monday, the first step in lowering debt supply as the federal government moves past its emergency-level response to the coronavirus pandemic. The move, which is well anticipated on Wall Street, will likely total an $800 billion cut in nominal auction sizes in the 2022 fiscal year compared with the 2021 fiscal year, according to estimates from NatWest. The majority of those cuts will come in securities with a 7-year duration or less, with a $2 billion per month cut in Treasury bonds with durations of 2, 3, and 5 years, and $3 billion per month cuts in 7, 10, and 20-year Treasuries, the bank estimates. "After ramping up coupon issuance to fund pandemic spending, it is now time for Treasury to start reducing issuance sizes commensurate with more normal deficits," said Meghan Swiber, a rates strategist at Bank of America Global Research. While the Treasury"s expected plans to lower bond supply will increase demand for shorter-duration bonds and steepen the yield curve, the reduction in debt issuance may be short-lived given the likelihood of that Congress will pass a Democrat-led $1 trillion infrastructure bill and a $1.75 trillion bill to address climate measures and social initiatives, said Scott Kimball, co-head of U.S. fixed income at BMO Asset Management. L1N2RO0ZK "From an issuance standpoint this is likely the calm before the storm," he said. The Treasury Department"s funding plans will also likely reflect the unsettled question of the debt ceiling, which constrains the U.S. government"s borrowing limit, said Gennadiy Goldberg, senior rates strategist at TD Securities. President Joe Biden signed legislation to increase the limit by $480 billion in mid-October, a short-term measure that pushed back the date by which the federal government is expected to exhaust its borrowing power to Dec. 3. "Despite the short-term debt ceiling increase, the Treasury is likely to remain heavily constrained by the ceiling. We look for bill supply to remain limited near-term but to ramp up after the ceiling is raised or suspended," by Dec. 3, Goldberg noted. The Treasury Department will announce its overall refunding plans on Monday and release details such as the size of next month’s auctions on Wednesday, the same day that the Federal Reserve is expected to announce its plans to taper its emergency-level support of the economy.