"We don't have to mix up the process of enlargement with reform of the common agriculture policy," Aznar told reporters after meeting Latvia's Prime Minister Andris Berzins during whistle-stop visits to Latvia and Lithuania on March 4 and 5.
Proposals in January by the European Commission, the EU's executive arm, are "rational and good," he said.
Meeting in Riga on Feb. 28, Baltic agriculture ministers called for a thorough rethink of the package of farm aid for the 10, mostly Central European, countries expected to join as soon as 2004.
The commission's proposals have caused dismay in candidate countries, as their farmers would receive direct payments initially at the level of just 25 percent of those received by current members, rising to the same level after a 10-year period.
The Baltic states are equally disappointed by proposed sales quotas, which would mean cutting production from today's levels as they were calculated on the basis of production levels during an agricultural slump in the late 1990s.
"I don't see how we can possibly decrease agricultural production," said Estonia's Agriculture Minister Jaanus Marrandi.
"This is a question of fair play in the medium and long term," said Latvia's Agriculture Minister Atis Slakteris.
"We can't say that a 10-year transition period is fair."
Such sentiments were echoed by representatives of 19 farmers' associations from the Baltic states and Poland who met in the central Latvian town of Sigulda on March 2 to discuss the commission's proposals.
"All EU members states should be treated equally from the moment of accession. Reference values used for calculations should be based on realistic data from the professional farming sector," said the associations in a written statement.
Despite difficult negotiations ahead on agriculture, the EU hopes to conclude membership talks this year to allow members to join as soon as 2004.
The Czech Republic, Estonia, Hungary, Latvia, Lithuania, Poland, Slovakia, Slovenia, Cyprus and Malta are all in a position to close membership talks this year.