Two 'Just Stop Oil' protesters in their twenties attacked the painting that suffragette Mary Richardson slashed in 1914, the group said in a statement.
Both the leaders stressed the need for preventing escalation, ensuring continued humanitarian aid and early restoration of peace and stability, the statement said.
The government also threatened action against the Israeli ambassador to South Africa over his recent remarks on the African country's stance on the Israel-Hamas war.
According to the Hamas-run health ministry in Gaza, 10,222 people have died including more than 4,000 children in the Gaza Strip since Israel launched its strikes in retaliation.