By Arafat Barbakh, Simon Lewis and Nidal al-Mughrabi GAZA/TEL AVIV/CAIRO (Reuters) -Pressure grew on Israel on Monday from its staunch ally the United States and from Middle East powers to ease its assault on Gaza as its forces said they engaged in “tough battles” against Hamas militants in central and southern parts of the enclave. Following talks with Arab leaders, U.S. Secretary of State Antony Blinken landed late Monday in Tel Aviv on the latest leg of a regional tour aimed at preventing the war – now entering its fourth month – from turning into a wider conflagration. Israeli officials ha…