PARIS (Reuters) - French President Francois Hollande's popularity rating has inched up from a record low this month, despite the heavy criticism he has received over security matters since the Bastille Day attack in Nice, a poll showed on Saturday.

Nineteen percent of those surveyed said they had a favorable opinion of Hollande, up from a record low of 18 percent in June, according to the BVA poll for Orange and Itele.

The poll was conducted on July 20-21, days after a delivery man in Nice killed 84 people when he drove his truck through a crowd of revelers leaving a July 14 fireworks display on the beachfront promenade.

With a presidential election due in nine months, conservatives lost no time in criticizing Hollande's Socialist government for not doing more about security following last November's terrorist attacks in Paris that left 130 dead.

His Prime Minister Manuel Valls, who was jeered by a crowd in Nice at a commemoration for the victims there, saw his popularity rating dip back to a record low of 24 percent from 25 percent in June.

Hollande's government has ordered an inquiry into policing on the night of the attack in the Riviera city in a bid to dispel criticism that security was inadequate.

Known for tough talk on security and immigration issues, conservative former president Nicolas Sarkozy saw his rating jump four percentage points to 24 percent.

That helped narrow some of the ground between him and Alain Juppe, his main rival to be the conservative Republicains' candidate for president.

Juppe, who is not seen as strong on security issues and was left scrambling to sound tough after the attack in Nice, saw his rating fall two percentage points to 42 percent, although he remained the most popular politician, according to the poll.

Marine Le Pen, leader of the anti-immigrant Front National party, saw her rating rise three percentage points to 27 percent after the Nice attack.

The attack led Hollande to reverse plans to end a state of emergency in place since the Nov. 13 attacks in Paris and instead extend it another six months, which lawmakers approved on Wednesday.

(Reporting by Leigh Thomas; Editing by Hugh Lawson)