Lionel Messi opened the scoring before a second-half brace from Luis Suarez ensured that Barca capped their Champions League victory earlier this year with the world title.

The first chance of the match fell Messi's way as he collected a pass from Andres Iniesta before being denied by fellow Argentine Marcelo Barovero.

River, the Copa Libertadores champions, held their own for much of the first half, but their resolve was broken 10 minutes before the interval.

Neymar got up well at the back post to nod the ball into Messi's path and he picked out the bottom corner with a prodded finish to score for Barca in three straight Club World Cup finals.

Suarez, who scored all three goals in Barca's semi-final win over Guangzhou Evergrande, missed a golden chance to make it two before the break, but he was soon on the scoresheet in the second half.

Sergio Busquets picked out the Uruguayan's run with a ball over the top and the number nine made no mistake this time.

River's heads seemed to go down after conceding the second and Barca dominated the rest of the contest.

Suarez's second, his 24th goal in his last 24 appearances, arrived midway through the second period when he headed home after Neymar produced an inch-perfect cross from the left.

River pushed for a consolation in the final 20 minutes, but Claudio Bravo kept the Argentinian side at bay.

With victory, Barca add the Club World Cup to their 2015 trophy haul that includes the La Liga, Champions League, Copa del Rey and UEFA Super Cup titles.