U.S. Democratic lawmakers vowed Friday to keep pressing for a vote on China currency legislation, now blocked by Republican leaders, which they said is vital for U.S. competitiveness in global markets.

``It is estimated that currency manipulation costs our economy over a million jobs,'' said Steny Hoyer, the No. 2 in the House of Representatives Democratic leadership. ``I urge the Republican leadership to put the currency bill on the floor.''

Earlier this week, the Senate voted 63-35 to pass a bill aimed at China by allowing companies to seek U.S. government ''countervailing duties'' against goods from countries with undervalued currencies.

The House is controlled by Republicans and the Senate by Democrats.

Many U.S. lawmakers contend that China undervalues its currency by as much as 15 to 40 percent to give its companies an unfair price advantage in international trade.

House Speaker John Boehner, a Republican, says he fears the bill could start a trade war and has refused to bring it to the floor for a vote, even though a similar measure passed the House last year 348-79.

``They don't want this bill on the floor for one reason: it would pass,'' said Representative Sander Levin, the top Democrat on the House Ways and Means Committee. ``The speaker should let the House work its will.''

Representatives Tim Ryan and Betty Sutton, two Democrats from Boehner's home state of Ohio, also said they had no intention of letting the issue drop.

Democrats hope Republican lawmakers will hear from constituents on the issue when they return to their districts next week.

The Obama administration says it shares the goal of the legislation, which is getting China to revalue its currency. But it has raised concern that some provisions in the Senate bill could violate World Trade Organization rules.

Meanwhile, the U.S. Treasury Department faces a Saturday deadline to issue an semi-annual report on whether any country is manipulating its currency for an unfair trade advantage.

The Obama administration, in five previous reports, has pushed China to move more quickly to revalue its currency. However, it has declined to take the step of formally labeling China a currency manipulator. (Editing by Vicki Allen)