ATHENS, Oct 31 (Reuters) - Greece's central bank said on Saturday it conducted a comprehensive assessment on small Greek lender Attica Bank, in line with the European Central Bank's health check of the country's four big banks.

The Bank of Greece said Attica Bank has a capital gap of 1.021 billion euros under the adverse scenario of the stress test and a shortfall of 857 million euros under the baseline scenario.

Attica Bank will submit a capital plan to the Bank of Greece on how it plans to cover its capital shortfall, the central bank said.

(Reporting by George Georgiopoulos)