* U.S. Congress to vote on human rights bill on Friday
* Russia has already agreed a "tough" response
MOSCOW, Nov 16 (Reuters) - Russia has agreed tough measures to respond to U.S. Congress if lawmakers pass legislation intended to punish Russian officials for human rights violations, a senior Foreign Ministry official said on Friday.
Congress will vote on a bill named after Russian lawyer Sergei Magnitsky on Friday - the third anniversary of his death in detention - which is designed to deny visas for Russian officials involved in his imprisonment, abuse or death.
Deputy Foreign Minister Sergei Ryabkov said Russia had already prepared its response but gave no more details than a Foreign Ministry statement on Thursday that warned of tough retaliation.
"Of course there are (measures in place). We have discussed (them) at all stages of the debate over the so-called Magnitsky bill," Interfax news agency quoted Ryabkov as saying.
"I can confirm that our response will be tough," he said, but did not specify what those measures would entail.
Lawmakers in the U.S. House of Representatives voted on Thursday 243-164 to include the legislation in a broader package to be put to a vote on Friday.
Magnitsky was jailed in 2008 on suspicion of tax evasion and fraud, charges which colleagues say were fabricated by police investigators he had accused of stealing $230 million from the state through fraudulent tax refunds. The Kremlin's own human rights council has said he was probably beaten to death.
His case has become a symbol of corruption and the abuse of citizens in Russia who challenge the authorities. But adoption of the bill could undermine efforts to improve relations at the start of U.S. President Barack Obama's new term and a few months into President Vladimir Putin's third term in Russia.