The United States last month secretly proposed a ban on some land-based missiles with multiple nuclear warheads but the Soviet Union said the plan was too limited, according to a published report. The New York Times reported in its Sunday editions that Soviet President Mikhail Gorbachev responded to the proposal last week, complaining that it excluded submarine-based ballistic missiles. A letter containing Gorbachev's reply was delivered to President Bush Friday by Soviet Foreign Minister Eduard Shevardnadze, the paper said, quoting administration officials it didn't name. The White House refused to confirm the offer or refusal, the Times said. The offer signals an attempt by Bush to put his stamp on arms reduction talks which thus far have followed proposals made during the Reagan Administration, the Times said. The rejection of the proposal caught the White House by surprise, the Times said, adding that Bush administration officials believe the Soviet Union's tougher position reflects a move by Soviet military officials to assert themselves. One unidentified White House official told the Times that Secretary of State James Baker III first presented the proposal to Shevardnadze last month in Namibia, where both were attending independence ceremonies. The proposal would ban mobile land-based missiles with multiple warheads, followed by the eventual elimination of all land-based missiles with multiple warheads. Administration officials said Moscow showed little interest in the first stage of the Bush plan, the Times reported. That first step, which could have been considered as part of the strategic arms treaty being negotiated this year, would have prevented the United States from deploying 10-warhead MX missiles on rail cars. It would have forced Moscow to remove its 10-warhead SS-24 missiles from railroad launchers and put them in stationary silos. The United States bases more of its ballistic missile warheads at sea, while the Soviet Union has most of its missiles on land.