Russia on Sunday expressed its deep concerns over the recent escalation of the Palestinian-Israeli conflict in the Gaza Strip.

"Moscow regards this recurrence of armed confrontation with anxiety. Any violence from which the civilian population suffers is absolutely impermissible and must be ruled out," said a statement posted on the Foreign Ministry's website.

Russia also called on both sides to show restraint and do their utmost to resume the Palestinian-Israeli negotiation process on a generally accepted ground, the statement said.

Some 20 Gazan residents have recently been killed as Palestinian militants kept launching rockets at Israel from the coastal enclave and Israeli war jets struck back.

The violence is the worst since August 2011, when 25 Palestinians were killed in a wave of violence after Israel killed Kamal al-Nairab, top commander of the pro-Hamas Popular Resistance Committees.

Direct Palestinian-Israeli negotiations resumed in September 2010 after a 20-month deadlock, but ran into impasse again after only two rounds of talks.