Brookfield Infrastructure Partners said on Monday it formally launched its hostile bid to buy Inter Pipeline Ltd, weeks after the Canadian oil and gas transportation company rejected its unsolicited offer as inadequate. Brookfield, which acquires and manages infrastructure assets, is offering C$16.50 per share for Inter, valuing Inter at C$7.08 billion ($5.62 billion). Earlier this month, Brookfield said it was willing to raise its offer to as much as C$18.25 per Inter share if the company had come to the negotiating table, but Inter turned it down and later launched a strategic review of options. Thee investment firm earlier this month also said it had acquired 19.65% economic interest in Inter Pipeline, to become the top shareholder in Calgary-based Inter Pipeline. Brookfield said on Monday other shareholders now have until June 7 to accept its offer at the original C$16.50 per share with an option to take that amount in cash or Brookfield’s shares. Inter Pipeline did not immediately respond to a Reuters request for comment. Inter, whose assets include more than 7,000 km (4,300 miles) of oil pipelines, 5 million barrels of oil storage in western Canada and natural gas liquids processing plants, said on Thursday its formal review could include a possible “corporate transaction” but no decisions have been made yet. Brookfield Infrastructure has engaged BMO Capital Markets and Barclays Capital Canada Inc to act as joint financial advisers.