Israeli Prime Minister Menachem Begin said last night that Foreign Minister Moshe Dayan will inform the government that Israel intends to enlarge its civilian settlements on the West Bank and the Golan Heights as soon as possible.

Begin met with his Likud bloc at the parliament building. He was quoted as saying, in reference to the Israeli plan for autonomy for Palestinian Arabs on the West Bank: " Autonomy has (assured) us (of border security and Jewish settlements. "

A Foreign Ministry spokesman last night confirmed Begin's remarks, but emphasized that they involved only enlargement of existing settlements, and not construction of new ones.

During the controversy after the Camp David summit over whether the agreed freeze on settlements was to last three months or five years, Israel emphasized that whatever the length of time, the freeze had nothing to do with expansion of existing settlements, the spokesman said.

Since then, several government officials have alluded to the need to " strengthen " Jewish settlements on the West Bank, but Begin's remarks last night appeared to be the first public indication by Israel that the government is formally notifying the U.S. government of its intentions.

Begin's remarks were interpreted here as a reaction to the visit earlier in the week by Assistant U.S. Secretary of State Harold Saunders, who met with Palestinian leaders on the West Bank to the chagrin of some Israeli leaders.