MOSCOW (AP) -- President Barack Obama says he trusts Russian Prime Minister Dmitry Medvedev to follow through on the agreements the two leaders have announced at their summit in Moscow.

The agreements include a preliminary deal to reduce both nations' stockpiles of nuclear warheads.

At a joint news conference Monday with the Russian leader, Obama said he's found Medvedev to be "straightforward" and "professional."

As for Tuesday's meeting with Russian Prime Minister Vladimir Putin, Obama said he understands that in the Russian government, Medvedev is the one who's in charge. But Obama says he's looking forward to getting a "full picture" of the needs and concerns of the Russian people.

He says it seems that Medvedev and Putin are working "very effectively" together.

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