Iraqi Prime Minister Nuri al-Maliki's assault against Shiite militants in the southern city of Basra was "bold" and demonstrates the growing capability of Iraq's security forces, US President George W Bush said Thursday, according to DPA. "Prime Minister Maliki's bold decision - and it was a bold decision - to go after the illegal groups in Basra shows his leadership and his commitment to enforce the law in an even-handed manner," Bush said. Al-Maliki's "bold decision to go after the illegal groups in Basra shows his leadership and his commitment to enforce the law in an even handed manner," Bush said in Dayton, Ohio. Bush accused Iran of backing the militants who had taken Basra as a stronghold until the offensive began earlier this week. Al-Maliki on Wednesday gave the militias 72 hours to surrender their arms. "Iraqi security forces are waging a tough battle against militia fighters and criminals in Basra, many of whom have received arms and training and funding from Iran," Bush said. Nearly 30,000 Iraqi troops are involved in the assault against the militias in Basra.