MADRID (Reuters) - Spain's Banco Sabadell (>> Banco de Sabadell SA) sees little chance of a rival bidder for TSB (>> TSB Banking Group PLC) emerging as it closes in on a takeover of the British bank, Chairman Josep Oliu said on Tuesday, adding he did not expect major regulatory obstacles for the purchase.

Sabadell, Spain's fifth-biggest bank, last week agreed a 1.7 billion pound ($2.53 billion) deal to buy TSB, in what would be one of the biggest cross-border banking acquisitions since the 2007 financial crisis.

Sabadell already effectively controls 30 percent of the lender thanks to a call option on the shares - which could put off potential competitors.

"It's very unlikely that competing offers (for TSB) will emerge, because the way the deal has been struck... we sort of already have 30 percent," Oliu told Reuters in a telephone interview.

It also has the backing of Lloyds (>> Lloyds Banking Group PLC), which had 50 percent of TSB.

Sabadell, a mid-sized Spanish lender based in the northeastern region of Catalonia, hopes the deal will help offset a lacklustre market at home, where the economy is emerging from a deep recession and lending is still weak.

It wants to grow TSB into a potent challenger to Britain's biggest banks, pitting it against domestic rival Santander (>> Banco Santander, S.A.), which already has a strong UK presence.

Banking analysts had warned that Sabadell's British ambitions may face regulatory obstacles, especially as the bank's capital levels will come under scrutiny.

Oliu dismissed these concerns. Sabadell is funding the deal via a 1.6 billion euro capital increase.

"Of course I'm confident (that it will go through), if not I would not have gone ahead," Oliu said.

Sabadell was one of the most acquisitive Spanish banks during a domestic financial crisis, and this experience of integrating lenders could help it with the TSB deal, Oliu added.

But the transaction was unlikely to spark a major wave of banking consolidation across Europe, he said, adding takeovers would likely be limited to lenders in the likes of Italy or Portugal which are struggling with weak capital levels.

"When these situations are resolved, that resolution will probably not come from within those countries, and could come from a bank from elsewhere," Oliu said. "But beyond that, I think it will be tough."

The successor to Portugal's state-rescued Banco Espirito Santo, Novo Banco, is among lenders currently in a sales process.

(Reporting by Jesus Agudo, Writing by Sarah White, Editing by Julien Toyer and Susan Thomas)