WASHINGTON – The Obama administration is launching a broad push for action on financial regulatory reform, returning to a key legislative priority even as the debate over healthcare consumes the U.S. Congress.

President Barack Obama's speech in New York on Monday, a year after the collapse of Lehman Brothers led to a worldwide financial crisis, will push for further measures to safeguard the financial system, officials said.

The president has put most of his domestic policy focus on the healthcare debate in recent months, drawing criticism from some who believed the regulatory reforms he proposed earlier this year were being shunted to the background.

Administration officials sought to counter that impression and indicated the Lehman anniversary would mark a roll-out of a new push to achieve reform this year.

We believe that this is the year, after what has happened, to overhaul the system of financial regulation and put in place a structure that can respond to the contemporary challenges, Obama's top economic adviser, Larry Summers, told reporters.

The reform would lay a basis for the kind of recovery and economic expansion that the president is seeking to create, Summer said, adding lawmakers could work on the measures simultaneously while hammering out a healthcare deal.

Obama will focus his speech on the need to strengthen the system to avoid another economic collapse, spokesman Robert Gibbs told reporters.

The speech on Monday will focus on the need to take the next series of steps on financial regulatory reform to ensure what happened a year ago ... doesn't happen again and cause the type of havoc that we've seen in our economy, Gibbs said.

The ambitious plan to overhaul U.S. financial regulation is bogged down in Congress. Proposed changes call for tighter regulation of banks and capital markets to better protect consumers.

The collapse of Lehman last year triggered the international financial crisis and accelerated Obama's race for the presidency. The Democrat, who made financial regulatory reform a key platform of his candidacy, was seen as having a cool, pragmatic reaction to the country's economic woes.

Lehman, once the fourth-largest U.S. investment bank, filed for bankruptcy protection on September 15, 2008, in the largest U.S. bankruptcy filing in history.

(Editing by Peter Cooney)