"The proposed solution is unsatisfactory because it would not help to protect ourselves even against the peak we had in the past," Nauseda said at a joint news conference with Romanian President Klaus Iohannis in Vilnius.
"The proposed conditions make it extremely difficult to take advantage of them,” he added.
Earlier this week, the EU's executive body proposed a gas price cap of 275 euros per megawatt hour for month-ahead TTF contracts.
However, the cap would only activate if prices exceeded that level for two weeks and the TTF price for liquefied natural gas would go above 58 euros for ten days within the two-week period.
Experts note that the cap is unlikely to be triggered, given that the 275-euro limit was exceeded for only a few consecutive days even at the peak of gas prices in late August.
Nauseda noted that "the market reacted less optimistically to the latest proposals (...) than to the European Council's decision".
"For me, this is a signal that we have to look for more effective ways to help member states survive this coming difficult winter," he said.
The president said he expects the Commission's proposals to be improved during Thursday's extraordinary meeting of EU energy ministers.