(Reuters) - The United Nations Security Council is due to meet on Sunday after Palestinian Islamist group Hamas launched the biggest attack on Israel in years on Saturday, diplomats said.

U.N. Secretary-General Antonio Guterres condemned the attack by Hamas and urged "all diplomatic efforts to avoid a wider conflagration, U.N. spokesperson Stephane Dujarric said in a statement.

"The Secretary-General is deeply concerned for the civilian population and urges maximum restraint. Civilians must be respected and protected in accordance with international humanitarian law at all times," Dujarric said.

(Reporting by Michelle Nichols; Editing by Ismail Shakil)